********
Microchip TCP/IP Stack Version Log:
********

Note: Please file bug-reports/bug-fixes at http://support.microchip.com/ or post 
      to the Microchip TCP/IP -> Ethernet Forum at http://forum.microchip.com/
      Look for stack updates at http://www.microchip.com/mal/

********
v5.36.2     July 2011
********
Changes:
1.  Removed the Google PowerMeter and Google PowerMeter EZConfig demos.  Google, Inc. 
    has deprecated Google PowerMeter and has expressed the intent to remove access to 
    it on September 16, 2011.  To obtain Microchip Technology's Google PowerMeter 
    reference implementation, you can download the June 2011 Microchip Application 
    Libraries archived release from www.microchip.com/mal.
2.  Modified the Energy Monitoring demo to remove Google PowerMeter functionality.
    The demo will still display measured power data on its internal web page.
3.  Updated the TCP/IP Stack Performance table to use the testing methodology from
    previous releases.  More information is available in the TCP/IP Stack Help file.
4.  gSnmpNonMibRecInfo[] has been moved from snmp.c file to CustomSNMPApp.c file and 
    SNMP_MAX_NON_REC_ID_OID macro has been moved from snmp.h file to CustomSNMPApp.c file.
    gSnmpNonMibRecInfo[] is used to list the static variables parent OID strings which are 
    not part of mib.h file. This structure is used to restrict the access to the SNMPv3 objects 
    from SNMPv2c and SNMPv1 version requests. Macro STACK_USE_SMIV2 is used to support 
    gSnmpNonMibRecInfo[] with MODULE-IDENTITY number. For V5.31 STACK_USE_SMIV2 need to commented.
5.  Removed the SPI2CON register freeze-on-halt bit macro from the SPIFlash, RAM, and EEPROM
    driver files to provide compatibility with C32 v2.00.
    
Fixes:
1.  Removed the MPFSImg2 files from the MPLAB X C18/C30 projects so that the projects
    will compile.  Disabled MPFSImg2.c for PIC32 Explorer 16 projects.
2.  Added a heap and minimum stack size for the PIC32 Ethernet Starter Kit MPLAB X
    project.
3.  The TCP/IP Stack Help File's performance table has been updated using the same
    test procedure used in previous releases.

Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  LCDBlocking.c timing for the LCD_E_IO enable signal is too fast to meet 
    published data sheet limits for various LCD controllers when compiling for 
    a PIC32 running at > 43MHz.  Despite this potential timing violation, the 
    LCD does normally work correctly on the precompiled PIC32 demos for the 
    Explorer 16 at 80MHz.
4.  For PIC32 implementations, depending on the configuration, it is possible that the
    MACGetFreeRxSize() returns a value greater than 64 KB.
    For backward compatibility reasons the stack uses a 16 bit value to check the returned value
    and it won't work corretly.
5.  Limiting the number of UDP sockets to 8 in the stack demos may prevent SNMP trap
    functionality.  If this occurs, you can increase the MAX_UDP_SOCKETS definition in 
    TCPIPConfig.h to 10 (if your system will support the increased data memory usage) 
    to fix this issue.
6.  The SNMP mib file's date and version parameter does not match the date/version of
    the current stack release.


********
v5.36       2 June 2011
********
Changes:
1.  Because of changes to the SHOUTcast server configuration, the Internet Radio
    demo is no longer functional.  This demo has been retained in the stack distribution
    to provide a TCP/IP code example.
2.  The UDP module will now perform address resolution and DNS querying automatically.
    As a result, the UDP module APIs have changed.  The UDPOpenEx function provides this
    additional functionality.  Please consult the TCP/IP Stack Help File's 
    "Stack API > UDP" topic for more information.
3.  The UDPOpen macro has been added to conform to the legacy UDPOpen interface.
4.  The Announce, BerkeleyAPI, DHCP client/server, DNS client/server, NBNS, Reboot,
    SNMP, SNTP, TFTPc, UDPPerformanceTest, and ZeroConf modules have been updated to
    use the new UDP API.  The iPerf demo has also been updated.
5.  The MPFS Classic and HTTP(1) modules have been removed from the stack.  Function-
    ality to support these modules has also been removed from the TCP/IP Stack software
    tools.  MPFS2 and HTTP2 are still supported.
6.  The UARTConfig demo module has been updated to upload MPFS2 images to the demo board
    in place of MPFS Classic images.
7.  To facilitate linking on PIC18 platforms, the number of UDP sockets in demo projects
    has been reduced from 10 to 8.
8.  The SNMP Stack application and mib2bib.jar PC utility now both support 1024
    dynamic IDs.
9.  SNMP_DEMO_TRAP is a new dynamic variable added to the snmp.mib file to support SMIv2 
    with TRAPv2.  This will correct a previously existing issue viewing traps with the
    iReasoning MIB browser.  As per those changes, the mchp.mib file has been modified 
    to support the SMIv2 standard.  This mib includes MODULE-IDENTITY which will provide
    MICROCHIP and MIB information.  snmp.mib also includes MODULE-IDENTIY(1), a new
    number (1) to the existing OID after ENTERPRISE-ID(17095).
10. Added a preprocessor check that will include the ultoa function if a version of the
    C32 compiler earlier than 1.12 is used.
11. Modified the WiFi module to use separate retry counters for AdHoc and Infrastructure
    modes.
12. Modified Berkeley API module to accept IPPROTO_IP as a valid protocol for the socket
    function.  The code will determine the protocol type from the socket type (datagram
    or stream).
13. Created MPLAB X projects corresponding to most MPLAB 8 projects and configurations.
    These projects are located in the MPLAB.X subfolder in the associated demo project
    directory.  The MPLAB X import wizard can be used to create MPLAB X projects from
    MPLAB 8 projects that don't have an analogue in the new demo project folders.
14. Added project support for the dsPIC33E and PIC24E architectures.
15. All TCP/IP Stack demo projects have been moved to the "TCPIP" subdirectory
    in the stack installation directory.
16. Created Java versions of several TCP/IP tools to provide cross-platform support. The
    TCP/IP Configuration Wizard has not been ported to Java; thus, it is only available
    for Windows users.
17. To prevent issues with path length, MPLAB 8 project names have been changed. 
    A list of the abbreviations used in the project names is available in the MAL help 
    folder (Microchip Solutions/Microchip/Help/Abbreviations.htm).  The names of the
    HardwareProfile and TCPIPConfig configuration files have been abbreviated as well.
18. Changed the configuration inclusion macros used by the TCP/IP Stack demo projects to
    match the terms used in the project/configuration names.
19. The "Alternative Configurations" subfolders in most demo projects has been renamed
    to "Configs."
20. Added a Google PowerMeter demo for use with the PIC18F87J72 Energy Monitoring PICtail.
21. The Web Preview tool is no longer included with the stack.

Fixes:
1.  Fixed a DHCP Server (DHCPs.c) lease leak problem that would occur when 
    STACK_USE_ZEROCONF_LINK_LOCAL was defined.  This problem would have 
    resulted in the DHCP server stop giving out any leases until being rebooted.
2.  Updated the PIC32MX6XX/7XX external PHY SMSC 8720LAN reference design. 
3.  Fixed bug with window expecting MACGetFreeRxSize() to return values < 32KB.
4.  Fixed a type casting bug with the CalcIPChecksum function that would cause 
    an incorrect TX checksum if the checksum value overflowed again after adding
    the carry bits to the checksum value.
5.  Fixed a bug in the AutoIP module that may have prevented the module from
    correctly defending its own address.
6.  Added a check to the Announce module to ensure the MAC layer is linked before
    attemping to transmit an Announce message.
7.  Fixed a bug in the ETH97J60 MACPut function.
8.  Added an additional preprocessor check in a debug menu setting in WF_Spi.c
    to prevent a build error.
9.  Added a fix to the Google PowerMeter demo code to restore SNTP timestamp
    sourcing if SNTP is enabled.  Previously, it would be overwritten by
    a possibly invalid HTTP timestamp.

Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  LCDBlocking.c timing for the LCD_E_IO enable signal is too fast to meet 
    published data sheet limits for various LCD controllers when compiling for 
    a PIC32 running at > 43MHz.  Despite this potential timing violation, the 
    LCD does normally work correctly on the precompiled PIC32 demos for the 
    Explorer 16 at 80MHz.
4.  For PIC32 implementations, depending on the configuration, it is possible that the
    MACGetFreeRxSize() returns a value greater than 64 KB.
    For backward compatibility reasons the stack uses a 16 bit value to check the returned value
    and it won't work corretly.
5.  Limiting the number of UDP sockets to 8 in the stack demos may prevent SNMP trap
    functionality.  If this occurs, you can increase the MAX_UDP_SOCKETS definition in 
    TCPIPConfig.h to 10 (if your system will support the increased data memory usage) 
    to fix this issue.
6.  The SNMP mib file's date and version parameter does not match the date/version of
    the current stack release.


********
v5.31       19 October 2010
********
Changes:
1.  Reorganized demo projects.  The TCPIP ENCX24J600 Demo App, TCPIP PIC32 ETH 
    Demo App, and TCPIP WiFi Demo App projects in stack versions 5.25 and prior 
    have all been merged into the TCPIP Demo App folder.  All four of these 
    projects were almost identical to each other, with the primary difference 
    being the network interface controller the projects were preconfigured to 
    support.  In this 5.31 TCP/IP Stack release, each hardware combination now 
    has its own MPLAB IDE project in the TCPIP Demo App folder.
2.  Reorganized HardwareProfile.h and TCPIPConfig.h structure for the TCPIP Demo 
    App, TCPIP Google PowerMeter Demo App, and TCPIP WebVend App projects.  Now, 
    instead of having one massive HardwareProfile.h file that supports a 
    multitude of hardware platforms simultaneously, simple individual 
    hardware profiles have been created for specific hardware combinations and 
    placed in the "Alternative Configurations" sub-folder.  The correct hardware 
    profile or TCPIP config file is selected by #including "HardwareProfile.h" 
    or "TCPIPConfig.h" as in previous stack versions.  However, the active 
    hardware profile or config file from the Alternative Configurations folder 
    is selected by a preprocessor macro defined in the MPLAB project settings 
    (passed on the command line to the compiler).
3.  Added HTTP_SAVE_CONTEXT_IN_PIC_RAM option to TCPIPConfig.h (HTTP2 server 
    module).  This option, when enabled, will increase HTTP2 server performance 
    when servicing multiple simultaneous connections at the expense of using 
    more PIC RAM.
4.  Added automatic TPIN+/- polarity swapping logic to ETH97J60.c driver for 
    PIC18F97J60 family devices.  Some 3rd party Ethernet switches, routers, and 
    end devices have their TX+/- pins wired backwards such that the remote TX+ 
    signal connects to the PIC TPIN- pin and the remote TX- signal connects to 
    the PIC TPIN+ pin.  Because 10BaseT Ethernet signaling is polarized and the 
    PIC18F97J60 family does not implement an auto-polarity feature, this 
    normally prevents all RX communications with these non-IEEE 802.3 compliant 
    link partners.  To work around this incompatibility, it is possible to 
    implement circuitry to swap the RX+ and RX- signals before reaching the 
    TPIN+ and TPIN- pins.  The PICDEM.net 2 Rev 6 reference design includes this 
    necessary circuitry (U6, U7, R54, and RX_SWAP GPIO output pin from PIC).  
    This stack version automatically controls the RX_SWAP signal based on the 
    ETH_RX_POLARITY_SWAP_TRIS and ETH_RX_POLARITY_SWAP_IO definitions in 
    HardwareProfile.h.  If these macros are undefined, then the automatic 
    polarity swapping feature is disabled in the ETH97J60.c driver.
5.  Added portable LFSRRand() and LFSRSeedRand() public functions to Helpers.c 
    and removed all references to C rand() and srand() functions.  The C rand() 
    function returns a 15 bit integer on 8 and 16 bit PICs, but a 31 bit integer 
    on PIC32s.  The LFSRRand() function returns a 16-bit integer, regardless of 
    which PIC you are using.
6.  Added support for various SST/Microchip brand SST25xxxxx SPI Flash chips to 
    SPIFlash.c driver.  Previously only devices supporting the Auto Address 
    Increment (AAI) Word Program opcode (0xAD) would work.  Now, devices such as 
    the SST2525VF010A should work, which require the AAI Byte program opcode 
    (0xAF) instead.
7.  Removed support for Spansion brand SPI Flash chips in the SPIFlash.c driver.  
    If your application is already using one of these devices, continue to use 
    the SPIFlash.c/.h files from TCP/IP Stack 5.25.  These older files are API 
    compatible with the current version, so can be dropped in by simply 
    overwriting the SPIFlash.c and SPIFlash.h files.
8.  Removed a -4 offset from the advirtised TCP Maximum Segment Size option 
    (MSS) and TCP_MAX_SEG_SIZE_RX configuration value in TCP.c.  The default 
    TCP MSS advertised is now 536 instead of 532.    
9.  For Wi-Fi projects in the TCPIP Demo App folder, changed 
    MY_DEFAULT_LIST_RETRY_COUNT to WF_RETRY_FOREVER instead of 3.  This
    changes default connection behavior to keep trying to connect instead of
    just trying 3 times which makes more sense for demonstration.
10. Changed WF_Connect() beacon timeout to 40.
11. IFConfig command in TCPIP WiFi Console Demo App modified to return 
    application-perspective MAC address from the AppConfig structure, and not 
    the Wi-Fi serialized MAC address (they may not match if user desired custom 
    MAC).
12. Updated the TCP/IP Configuration Wizard.  The user can now configure 
    wireless settings and stack settings seperately.  Because of the changes to 
    the TCPIPConfig.h file, the user must now select the specific copy of 
    TCPIPConfig.h (or any of its variants) instead of selecting a project 
    directory. Added the ability to select WF_RETRY_FOREVER in the Wi-Fi 
    configuration settings.  Added a selection parameter for BSD socket count. 
    Added validation to check for the proper number of Berkeley sockets and TCP 
    performance test sockets in the socket configuration screen (Advanced 
    Settings) if either of these features are enabled.  Added the ability to 
    create sockets of the same type with different TX/RX buffer sizes in the 
    socket configuration screen.
13. Updated the TCPIP WebVend Demo App to support Wi-Fi in several 
    configurations.
14. Modified the Google PowerMeter demo to automatically determine the 
    date/time from the HTTP module if the date/time cannot be obtained from the 
    SNTP module.
15. Added a new Google Map project example to the Combo Demos folder.  This 
    example runs on a PIC24FJ256DA210 Development Board + Fast 100Mbps Ethernet 
    PICtail Plus (or Ethernet PICtail Plus) + Truly 3.2" 240x320 display, 
    TFT_G240320LTSW_118W_E (or Powertip 4.3" 480x272 display, 
    PH480272T_005_I11Q).  It also can run on the PIC32 Multimedia Expansion 
    Board + PIC32 Ethernet Starter Kit.  This demo connects to the Internet, 
    sends an HTTP query for a specific map tile to the Google Static Maps API, 
    and then displays the compressed tile to the graphics display.  For more 
    information, see the "Getting Started - Running the Graphics Google Map 
    Demo.htm" file in the Combo Demos\Google Map folder.
16. Added preliminary SNMPv3 module.  This module, enabled with the 
    STACK_USE_SNMPV3_SERVER option in TCPIPConfig.h, implements the Simple 
    Network Management Protocol, version 3.  Among other things, SNMPv3 adds 
    secure authentication and cryptographic privacy as compared to SNMPv2C.  
    This implementation currently only supports AES encryption (no DES support).  
    It also has only been tested with the PIC32 Ethernet Starter Kit (TCPIP 
    Demo App - C32 - PIC32_ENET_SK_DM320004_INTERNAL_ETHERNET.mcp MPLAB IDE 
    project).  SNMPv3 on PIC18, PIC24, and dsPIC platforms are not supported at 
    this time.  Because AES encryption has specialized United States export 
    requirements, this TCP/IP Stack release does not include the required AES 
    library to enable SNMPv3.  To obtain the needed AES library, you must 
    purchase SW300052 v2.6 or later.  Older v2.5 and previous versions include 
    AES related files on them, but do not include the new AES files required by 
    SNMPv3.  For more information on using SNMP, refer to the TCP/IP Stack Help 
    (Demo Information -> Available Demos -> TCPIP Demo App -> Demo Modules -> 
    Network Management (SNMP) Server).
17. Altered the SaveAppConfig() function in MainDemo.c to store a more robust 
    signature to EEPROM/SPI Flash when saving the AppConfig structure.  In v5.25 
    and prior stack versions, when EEPROM or SPI Flash memory was available, the 
    stack would automatically write a one byte marker character to address 
    0x000000 in the EEPROM/Flash indicating if a valid AppConfig structure was 
    stored in the non-volatile memory.  This resulted in the EEPROM/Flash 
    contents being organized like the following:
        Address                 Data Contents
        ===================     ==============================================
        0x000000:               Marker Byte
        0x000001:               AppConfig structure
        MPFS_RESERVE_BLOCK:     Start of MPFS/MPFS2 image containing web pages
    In this stack version, EEPOM/Flash contents will now contain:
        Address                 Data Contents
        ===================     ==============================================
        0x000000:               Length of AppConfig structure (16-bit integer)
        0x000002:               IP checksum of the AppConfig default values, as 
                                defined in TCPIPConfig.h and WF_Config.h 
                                (16-bit integer).
        0x000004:               IP checksum of the subsequent EEPROM/Flash 
                                bytes of the AppConfig values.
        0x000006:               AppConfig structure
        MPFS_RESERVE_BLOCK:     Start of MPFS/MPFS2 image containing web pages
   The additional checkums allow automatic detection to occur if you change one 
   of the values in TCPIPConfig.h or WF_Config.h that affects AppConfig.  If 
   you change one of the values in code, then upon boot up, the application 
   will automatically detect this change and start using the values that you 
   selected in code.  If, at run time, you decide to change the AppConfig 
   values and commit the changes to EEPROM/Flash, then the stack will 
   subsequently use the run-time saved values on future reboots.  The checksum 
   at offset 0x000004 ensures that if any corrupted AppConfig contents are 
   found in EEPROM/Flash (ex: power is lost between writing the signature 
   structure and actual AppConfig structure, or code unintentionally overwrites 
   something in the AppConfig memory area), then the original defaults defined 
   in TCPIPConfig.h and WF_Config.h will be used instead of the corrupted 
   values.  This EEPROM/SPI Flash change affects all projects except TCPIP 
   Internet Radio App, TCPIP Internet Bootloader App, and all PIC32 Starter Kit 
   projects since these projects do not have or use external EEPROM or SPI 
   Flash memory.


Fixes:
1.  Fixed a UDP bug in which a transmitted packet would have been addressed 
    to the wrong destination node if the UDP socket received a broadcast packet 
    from a different remote node from the last received packet, but using the 
    same source port number as the last received packet.  The 
    FindMatchingSocket() function in UDP.c will now always change the local 
    socket parameters to send to the most recent remote node's unicast IP 
    address, regardless of if the last received packet was addressed to a 
    multicast or broadcast destination.  Thanks go to Billy Walton for reporting 
    this erroneous behavior.  If you wish to change the destination IP/MAC 
    addresses or port number for a UDP packet that you are ready to send, write 
    the new parameters to the UDPSocketInfo[SocketHandle] global structure 
    before calling UDPFlush().  This structure contains remoteNode and 
    remotePort parameters for the remote IP address/MAC address and remote UDP 
    port, respectively.  You can also read these values to obtain the remote 
    addressing parameters for the last received packet on the given UDP socket.  
    Note that "SocketHandle" refers to the UDP socket handle returned by the 
    UDPOpen() API, not the literal string "SocketHandle".
2.  Fixed ADC state save/restore bug in GenerateRandomDWORD() function in 
    Helpers.c.  PIC24, dsPIC, and PIC32 platforms require the ADC ON/ADON bit to 
    be cleared before modifying certain other ADC register contents.
3.  Fixed an ENC28J60 MAC/MII register write timing violation when using a 
    PIC24H or dsPIC at over 33MIPS.  There was inadequate Chip Select hold time 
    provided, violating the 210ns minimum specified in the ENC28J60 data sheet.  
    This violation may have resulted in certain devices losing the ability to 
    receive packets (due to the MARXEN bit, MACON1<0>, getting cleared 
    unintentionally).
4.  Fixed an ENCX24J600.c driver bug in which operating at 100Mbps with the 
    ENC424J600/624J600 Ethernet controller, it would be possible for the 
    MACGetHeader() function to issue a Reset() operation under rare 
    circumstances.  The PIC would reset whenever the PHY detected an illegal 
    symbol during 4B5B decoding but guessed the correct 4B symbol such that no 
    data corruption or CRC error occurred.  This condition results in a valid 
    packet being received but with the Received Ok Receive Status Vector bit 
    being clear (RSV<23> == 0).  This issue would become more probable when 
    using very long Ethernet cables (ex: 100 meters) and receiving a lot of 
    data.
5.  Fixed a TCP bug in which calling TCPDisconnect() to close a connection when 
    the remote node's RX window was 0 bytes would have caused the stack to enter 
    an infinite loop sending duplicate ACK packets.
6.  Fixed Wi-Fi bug that caused assert condition if too many management messages 
    were being received during data traffic.
7.  Fixed Wi-Fi bug that caused WF_EVENT_CONNECTION_RESTABLISHED event case to 
    send the wrong notification to the app.  
8.  Fixed Wi-Fi bug that caused assert failure with Scratch move failure.
9.  Fixed Wi-Fi bug in WF_CAGetChannelList() and WF_CAGetSecurity that caused 
    failure.
10. Fixed Wi-Fi EasyConfig bug that required development boards to be manually 
    reset even after new network was selected.
11. Fixed MRF24WB0 bug that caused assert if invalid WPA/WPA2 key was entered.
12. Fixed Wi-Fi power management bit behavior in PS-Poll frame that was causing 
    some AP’s to never send data or disconnect when in power save mode.
13. Fixed a TCP bug in which attempting to open a client TCP socket to a remote 
    server, specified by IP address (not DNS address), that was offline, but 
    who's MAC address was already cached by the ARP client, would result in 
    endless back-offs. For example, when attempting to contact the remote node 
    (that was not responding), the TCP module would have transmitted a SYN at 
    time T=0 seconds, T=1s, T=3s, T=7s, T=15s, T=31s, T=63s, T=127s, T=255s, 
    etc.  The exponential back-off between retransmissions would grow 
    indefinitely until the retransmission interval would have grown so large 
    that effectively no-retransmissions would be occurring.  Assuming the 
    application wasn't written with its own timeout to prevent endless waiting, 
    this would prevent the socket from automatically establishing the 
    connection to the remote server once the server came back online.  With this 
    TCP fix, the exponential back off now saturates after TCP_MAX_RETRIES (5) 
    back offs and continues to retransmit using the same interval.  By default, 
    this means SYN transmissions will occur at T=0 seconds, T=1s, T=3s, T=7s, 
    T=15s, T=31s, T=63s, T=95s, T=127s, etc.  After 5 back-offs the 
    retransmission interval stops growing and stays constant at 32 seconds.
14. Fixed an RSA computation bug that would cause the RSA module to never 
    complete if you attempted to compute y = x^e % n where e = 3 (or similar 
    number < 256 with only 0, 1, or 2 bits set).  Thanks go to Kevin Maidment 
    for pointing this error out and suggesting a solution.  Note, that this fix 
    to RSA.c is not distributed with the ordinary TCP/IP Stack due to United 
    States export restrictions.  To get this fix, you must repurchase SW300052.  
    This fix is included in SW300052 v2.6 or later.  If you don't have CD media 
    to identify the SW300052 version that you have, you can test the RSA.c file 
    that you have.  RSA.c in SW300052 v2.6 has a CRC32 checksum of 0x91F66711.  
    RSA.c in v2.5 and prior had a checksum of 0xB1E8B0CC.


Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  LCDBlocking.c timing for the LCD_E_IO enable signal is too fast to meet 
    published data sheet limits for various LCD controllers when compiling for 
    a PIC32 running at > 43MHz.  Despite this potential timing violation, the 
    LCD does normally work correctly on the precompiled PIC32 demos for the 
    Explorer 16 at 80MHz.



********
v5.25       07 May 2010
********
Changes:
1.  Added support for the Microchip MRF24WB0 802.11 WiFi controller (module 
    part number MRF24WB0MA).  This product is intended as a backwards 
    compatible, drop in replacement to the ZG2100.  The MRF24WB0MA should work 
    with previous TCP/IP Stack versions as if it were a ZG2100M, but when the 
    MRF24WB0MA is used with this (5.25) and future TCP/IP Stack versions, 
    feature improvements inside the MRF24WB0 allow the TCP/IP Stack code/RAM 
    size to be smaller and run faster.  
2.  Dropped support for the ZeroG ZG2100 802.11 WiFi controller.  Applications 
    that must stay with this device should continue to use TCP/IP Stack 
    version 5.20b or earlier.  All new projects or preexisting projects 
    undergoing updates should be developed with the MRF24WB0 instead.
3.  The WiFi connection management state machines now run on the MRF24WB0 
    instead of the PIC host, freeing up code and data space.  Connection profiles 
    can be created and the connection algorithm fine-tuned by the PIC 
    application. In the WiFi demos see the WF_Connect function in MainDemo.c for 
    an example of how to configure and then establish a WiFi connection.  The
    programming model has changed to an API model which is documented in 
    'TCPIP Stack Help.chm'.
4.  Changed "VERSION" macro definition in TCPIP.h to "TCPIP_STACK_VERSION".  
    "VERSION" is overly generic and will likely conflict with other identical 
    tokens one may use in their application code or source libraries.
5.  Added support for the PIC24FJ256GA110, PIC24FJ256GB110 and PIC24FJ256GB210
    PIMs for the Explorer 16.  Note that when using the PIC24FJ256GA110 
    general purpose PIM, the Ethernet PICtail Plus, Fast 100Mbps Ethernet 
    PICtail Plus, MRF24WB0MA Wi-Fi PICtail Plus, or other SPI PICtail daughter 
    board should be installed in the middle SPI2 slot of the Explorer 16, not 
    the ordinary topmost SPI1 slot used by other PIMs, including the 
    PIC24FJ256GB110 and PIC24FJ256GB210 ones.  The software is set up to use 
    SPI2 for the PIC24FJ256GA110 PIM to avoid incompatibilities with silicon 
    revision A3, which does not allow the SCK1 pin to be configured as a PPS 
    output.
6.  Added support for the PIC24FJ256DA210 Development Board.
7.  Added TFTPUploadRAMFileToHost(), TFTPUploadFragmentedRAMFileToHost() and 
    TFTPGetUploadStatus() APIs to the TFTPc.c file.  These APIs provide a very 
    simple means of uploading a whole file to a remote TFTP server without 
    requiring a great deal of application state machine logic.  These APIs 
    require the DNS client module to be enabled (STACK_USE_DNS must be defined, 
    in addition to STACK_USE_TFTP_CLIENT).
8.  Added a dummy DNS Server module.  This server always sends the local IP 
    address in response to all queries received.  When using the PIC DHCP 
    server, its purpose is to allow a user to type anything into a web browser 
    (ex: http://asdf/) and still receive the web page provided by the PIC, much 
    as a hotel or airport WiFi router will serve to you before you've paid or 
    agreed to the network's terms of service.  This DNS server module is 
    implemented in DNSs.c, requires one UDP socket, and is enabled via the 
    STACK_USE_DNS_SERVER option in TCPIPConfig.h.
9.  Changed SPIFlash.h file defaults to target an SST SPI Flash with 4096 byte 
    sectors instead of a Spansion Flash with 65536 byte sectors.  These new 
    defaults are, among other reasons, in support of the PIC24FJ256DA210 
    Development Board, which has an SST SST25VF016B on it.
10. Made TCP Keep-Alive packets consistently get sent TCP_KEEP_ALIVE_TIMEOUT 
    (default 10 seconds) after the last socket TX or RX activity.  In earlier 
    stack versions, if the local node transmitted some data and then let the 
    socket go idle, the first Keep-Alive packet sent would use the 
    TCP_START_TIMEOUT_VAL (default 1 second) timer value before getting sent.  
    While benign in terms of application behavior, these faster than normal 
    keep-alive transmissions were distracting when viewed in Wireshark or other 
    packet capture tools.
11. Disabled STACK_USE_DYNAMICDNS_CLIENT option in TCPIPConfig.h by default for 
    the TCPIP Demo App and TCPIP ENCX24J600 Demo App projects.  This option was 
    enabled by default in earlier stack releases.  This was done to save code 
    size and allow out-of-box compilation on devices with 128KB of Flash when 
    not using compiler optimizations.  The TCPIP PIC32 ETH Demo App project 
    continutes to have this option enabled by default.
12. Added SNMP v2 TRAP PDU format.  Macro SNMP_STACK_USE_V2_TRAP is used to 
    enable the SNMP v2 trap format.  New API function SNMPV2TrapDemo() is 
    included to support more than one variable binding to the SNMPv2 TRAP. This 
    API can be used for a single SNMPv2 TRAP variable varbind and is part of 
    CustomSNMPApp.c. A multiple variable binding demo can be enabled 
    MainDemo.c.  One should not enable both SNMPTrapDemo and SNMPV2TrapDemo 
    simultaneously.  Global flag "gSetTrapSendFlag" is used to indicate the 
    start and end of SNMPv2 trap varbinds.  If gSetTrapSendFlag is FALSE, then 
    very next variable varbind for the SNMPv2 TRAP, is the last or only one 
    variable varbind.  If gSetTrapSendFlag is TRUE, then there is another 
    variable varbind available to be part of the SNMPv2 TRAP PDU.
13. Added support for PIC32MX6XX/7XX external PHY's: SMSC 8700LAN and National 
    DP83640.
14. Added schematics and BOM for the PIC32 Ethernet Starter Kit.
15. Added the Google PowerMeter demo project. Consult the "Reference 
    Implementation for Google PowerMeter.chm" help file for more information.
16. Modified the SSL and TCP modules to create the TCPStartSSLClientEx function.
    This function will enable the SSL module to store supplementary data
    (currently only SSL Certificate Public Keys) in a structure.
17. Moved the HTTP_PORT, HTTPS_PORT, HTTP_MAX_DATA_LEN, and HTTP_MIN_CALLBACK_FREE
    macros from HTTP2.c to TCPIPConfig.h.


Fixes:
1.  The SPIFlashEraseSector() function in the SPIFlash.c file incorrectly erased 
    the sector specified by the current write pointer (set by calling 
    SPIFlashBeginWrite()) instead of the specified dwAddr parameter address.  
    This error had no impact on any TCP/IP Stack code as these parameters always 
    matched.  However, application code using the API would have been affected.  
    Thanks go to Marc Boon for reporting this issue on the Microchip Ethernet 
    forum.
2.  Fixed ENC424J600/624J600 driver for PSP modes 2, 4, 6, and 10.  The PIC's 
    PMP PMMODE<9:8> bits were not set correctly.
3.  Removed from lingering references to TickGetDiff() in FTP.c, TFTPc.c and 
    UARTConfig.c.
4.  Fixed DNS client module from returning the DNS server IP address if the DNS 
    query failed due to a server error (i.e. DNS did respond, but did not 
    return any records, such as when attempting to resolve a name that isn't in 
    the DNS).  DNSIsResolved() will now return 0.0.0.0 on any non-recoverable 
    DNS error or timeout.
5.  Fixed HTTP2 MPFS upload page being accessible from URLs that weren't an 
    exact match.  For example, in 5.20 and earlier, accessing 
    http://mchpboard/mpfsuploadASDF would still have opened the mpfsupload page.  
    Thanks go to Andrea Rivolta on the Microchip Ethernet Forum for identifying 
    this error.
6.  Improved UDP TX checksum code for the special case when the computed 
    checksum was 0x0000.  According to the UDP RFC, for this corner case, the 
    checksum should be converted to 0xFFFF before transmission to differentiate 
    from the checksum disabled case, improving error detection by a minuscule 
    amount.
7.  Fixed GetCLKOUT() function in ENCX24J600.c driver file.  Previously, 0x00 
    would always be returned, regardless of the value in the COCON bits of 
    ECON2.  The function documentation for SetCLKOUT() and GetCLKOUT() was also 
    corrected (had obsolete information ported over from ENC28J60 driver file).
8.  Fixed DHCP client rebinding bug in which the DHCP client would request the 
    wrong IP address if an unrelated DHCP OFFER or ACK message were received 
    after we transmitted a DHCP REQUEST but before we received our DHCP ACK. 
    Under rare conditions, this would have resulted in the TCP/IP stack 
    reverting to the static or AutoIP assigned address for a few seconds 
    between DHCP lease renewals.
9.  Fixed TFTP Internet Bootloader bug in which uncommon .hex files containing 
    a certain data pattern could not be uploaded correctly to the PIC18F97J60 
    family device.  For these problem .hex files, a block of 32 program words 
    (64 bytes) would remain unprogrammed (left as 0xFFFF) due to a parsing error 
    in the bootloader's DecodeHex() function.  The TFTP upload operation would 
    succeed without reporting a programming error.  The problem can be detected 
    by using an ICD3 or similar ICSP programmer and reading the program Flash 
    out of a device that is programmed with the bootloader and application .hex 
    files.  Compare the resulting memory dump to a device programmed only with 
    the application .hex file.  If you have devices deployed in the field with 
    the previous bootloader and happen to generate a  problem application .hex 
    file, you can potentially work around the bootloader bug by opening the 
    application .hex file with Notepad and appending dummy address records to 
    the beginning to move the data around in the file.  For example, at the very 
    top of the .hex file, add lines containing ":020000040000FA" until the 
    bootload process works correctly.  You may alternatively try adding spaces 
    at the end of any line, although this may make the .hex file incompatible 
    with some programming utilities.  Thanks go to Jonathan Seidmann for 
    identifying and reporting this bug.
10. Fixed SNMPv2 TRAP format issue where SNMP browser was displaying all the 
    SNMPv2 traps as SNMP version 1.  SNMP v2 TRAP pdu format is rectified.  
    Macro SNMP_STACK_USE_V2_TRAP is used to form and send a SNMPv2 TRAP PDU.  
    SNMPTrapDemo API is used for both SNMPv1 and SNMPv2 single variable 
    varbind trap.
11. Fixed an HTTP2.c server module initialization bug when using the 
    PIC32MX7XX/6XX series internal Ethernet module.  During initialization the 
    HTTPLoadConn() function would overwrite over 100 bytes of PIC RAM past the 
    end of the reserved memory allocated for the HTTP2 module.  This problem 
    would manifest itself by locking up the TCPIP PIC32 ETH Demo App-C32 demo 
    shortly after power up if you compiled TCP/IP Stack version 5.20 with the 
    MPLAB C Compiler for PIC32 MCUs (C32) version 1.11.
12. Fixed SSL client from incorrectly parsing for the server's public key in 
    rare cases where the RSA Public Key Algorithm identifier was received, but 
    the key hadn't been received by TCP yet.  Thanks go to Kevin Maimdnet for 
    identifing this error in SSL.c and reporting it via 
    http://support.microchip.com/.
13. Fixed Tick.c TickGet(), TickGetDiv256() and TickGetDiv64K() APIs sometimes 
    returning the wrong value on PIC32 platforms.  On the PIC32MX3XX/4XX family 
    devices a wrong return result would sometimes occur if using -O3 compiler 
    optimizations (maximum speed) with the Microchip MPLAB C Compiler for PIC32 
    MCUs (C32).  On the PIC32MX5XX/6XX/7XX family devices, such as the 
    PIC32MX795F512L device used on the PIC32 Ethernet Starter Kit, wrong values 
    could be returned, regardless of the compiler optimization level.


Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  HI-TECH PICC-18 compilers are not supported in this release.  The supplied 
    HI-TECH PICC-18 MPLAB projects usually will not compile and/or link.
4.  LCDBlocking.c timing for the LCD_E_IO enable signal is too fast to meet 
    published data sheet limits for various LCD controllers when compiling for 
    a PIC32 running at > 43MHz.  Despite this potential timing violation, the 
    LCD does normally work correctly on the precompiled PIC32 demos for the 
    Explorer 16 at 80MHz.



********
v5.20       18 November 2009
********
Changes:
1.  Added PIC32MX7XX/6XX Family integrated Ethernet controller support.  The 
    "TCPIP PIC32 ETH Demo App" folder was added to compile for the PIC32 
    Ethernet Starter Kit.  Ethernet driver files "ETHPIC32ExtPhy.c" and 
    "ETHPIC32IntMac.c" were added, in addition to the "ETHPIC32ExtPhyDP83848.c" 
    file, which is a specific driver file for the National DP83848 10/100 PHY.
2.  Added RFC 3927 Auto IP module.  This module will automatically assign a 
    local IP address to the node in the 169.254.xxx.xxx private address range 
    (subnet mask 255.255.0.0) if a DHCP server is not present on the network or 
    the DHCP client is disable.  The exact IP address chosen will be 
    pseudo-random, but as required by the protocol, it will perform gratuatous 
    ARPs to avoid clobbering anyone else's IP address.  Also, unless there is an 
    address collision with a preexisting node on the network, the IP address 
    generated by the Auto IP module will not change between power cycle events 
    (random number generator is seeded by local MAC address).  To enable this 
    module, STACK_USE_AUTO_IP must  be defined in TCPIPConfig.h.  When compiled 
    in, the module defaults to enabled, but will automatically yield to the 
    DHCP client module, which has higher priority.
3.  Added "TCPIP MDD Demo App" beta application projects.  Projects in this 
    folder store the HTTP2 web pages in external FAT16/FAT32 formatted SD card 
    or USB Mass Storage media instead of an MPFS2 formatted EEPROM or SPI Flash.  
    For more information on these projects, see the "Running the TCPIP MDD Demo 
    App (Beta Release).pdf" file in the Microchip\Help folder.
4.  Expanded XEEReadArray() API's third length parameter from a BYTE to a WORD.
5.  Converted all variable declarations and type casts of TICK data type to 
    DWORD.  The TICK typedef is now deprecated and will be removed in a future 
    stack release.  This data type conflicts with the TICK structure used in 
    certain other Microchip software libraries.  
6.  Added TCP_WINDOW_UPDATE_TIMEOUT_VAL option to the TCP.c file (default 
    200ms).  This timeout controls the time after calling TCPGet() or 
    TCPGetArray() before the stack will transmit a RX window update to the 
    remote node.  Historically, the TCP_AUTO_TRANSMIT_TIMEOUT_VAL value was 
    used for this purpose (default 40ms).  This change decreases the net window 
    update transmission overhead.  If this adversely affects your application 
    RX performance (unlikely, but possible for certain communications patterns), 
    set TCP_WINDOW_UPDATE_TIMEOUT_VAL equal to or shorter than 
    TCP_AUTO_TRANSMIT_TIMEOUT_VAL to get the same or better behavior relative 
    to previous stack versions.
7.  Split TCP_MAX_SEG_SIZE configuration constant in TCP.c into separate 
    TCP_MAX_SEG_SIZE_TX and TCP_MAX_SEG_SIZE_RX configuration constants.  
    Previously, TCP_MAX_SEG_SIZE was used to limit both the maximum size of 
    transmit and receive packets.  In cases where large TX FIFOs are allocated, 
    and the remote node advirtises a large Maximum Segment Size TCP option, this 
    change improves TCP transmit performance by roughly 10%.
8.  Renamed "Internet Radio App", "Internet Bootloader App" and "WiFi Iperf 
    App" folders to "TCPIP Internet Radio App", "TCPIP Internet Bootloader App"
    and "TCPIP WiFi Iperf App" respectively.  These new names ensure consistent 
    folder placement when viewing the Microchip Solutions folder with other 
    Microchip Application Libraries installed.

Fixes:
1.  Fixed SSL functionality (ex: HTTPS server) from failing when using the 
    ENC424J600 and ENC624J600 Ethernet controllers.  In stack versions 5.00 and 
    5.10, the BFSReg() and BFCReg() functions were being incorrectly used to set 
    and clear CRYPTEN (EIR<15>).  ENC424J600/624J600 silicon errata #6 on 
    production silicon revision A2 prevents BFSReg() and BFCReg() from being 
    able to modify CRYPTEN.  This resulted in the SSL RSA encrypt/decrypt 
    operations from ever finishing.  The ENC424J600/624J600 errata #6 workaround 
    is now implemented in the ToggleCRYPTEN() function in ENCX24J600.c.
2.  Fixed an RSA padding error in the ENCX24J600.c's version of RSASetData() and
    RSASetE() functions.  This fixes the Bad Record MAC problem when using SSL 
    client APIs with the ENC424J600 and ENC624J600, as mentioned in the 5.10 
    stack release notes' Known Problems section.  Although unknown at the time 
    of release this problem also occurred in stack version 5.00.
3.  Fixed DNS client from mishandling DNS responses that did not use name 
    compression.  Thanks go to Will Stone on the Microchip Ethernet forum for 
    identifying this bug.
4.  Fixed an ExtractURLFields() API bug which would incorrectly parse the URLs 
    containing other URLs.  Ex: 
    "http://www.google.com/search?q=http://www.microchip.com/"
5.  Fixed TickGet(), TickGetDiv256(), and TickGetDiv64K() APIs from potentially 
    returning an incorrect time value (0x10000 ticks less than it should have) 
    on rare occasions when using a PIC32 and with compiler optimizations turned 
    on.  The Tick.c module was also revised so that the IEC0 register does not 
    get written to via a load-modify-store operation on PIC32s so that it is 
    now possible for other application ISR functions to write to IEC0 without 
    risking state corruption.
6.  Fixed PIC32 Starter Kit Debugger losing access to the PIC32 target when the 
    project was run.  JTAG was being disabled at run time, but the PIC32 
    Starter Kit Debugger requires JTAG to communicate with the debug 
    executive.  JTAG is now conditionally disabled on PIC32s when the 
    __MPLAB_DEBUGGER_PIC32MXSK macro is undefined.
7.  Fixed a Berkeley sockets API bug in which calling closesocket() on a 
    SOCK_STREAM type socket (TCP) did not actually close the socket if the 
    remote node did not first send a FIN to the local node. This would leak a 
    TCP socket each time the affected API calling sequence occurred and result 
    in no FIN getting transmitted to the remote node.
8.  Fixed an HTTP2 filename parsing bug that would occur when a web browser 
    submitted a request for a file with hex encoded characters in it.  For 
    example, with stack version 5.10 and Firefox 3.5.3, typing 
    "http://mchpboard/%70rotect" into the URL field would have resulted in an 
    HTTP 404 not found error when "http://mchpboard/protect/index.htm" should 
    have been returned instead.  Thanks go to Steve Tuttle for reporting this 
    issue and suggesting a solution.
9.  Fixed a Berkeley sockets API bug in which calling recvfrom() on a datagram 
    type socket (UDP) would return an incorrect remote IP address and port 
    number when the from pointer was non-NULL.
10. Fixed HTTP2 server bug in which the HTTPReadPostName() function was failing 
    to convert the field name from URL encoding to plain-text.  If the browser 
    posted, for example, a field named "Stock Remaining", it would have been 
    incorrectly returned from HTTPReadPostName() as "Stock+Remaining".
11. In Stack 5.10, any new values you saved into AppConfig via the Network 
    Configuration demo web page would have been mishandled for WiFi projects.  
    HTTPPostConfig() in CustomHTTPApp.c of the TCPIP WiFi Demo App and TCPIP 
    Iperf Demo App projects were corrected so that they now write a magic 0x61 
    marker into EEPROM/SPI Flash address 0x0000 to inidicate that the AppConfig 
    structure is valid in EEPROM/SPI Flash.  This prevents the InitAppConfig() 
    function in MainDemo.c from restoring the default settings when changing 
    the values through the Network Configuration page.
12. For WiFi projects, a Gratuitous ARP Work-around was implemented to work 
    around cases where access points send broadcast messages at data rates that 
    the ZG2100 cannot listen to. The define USE_GRATUITOUS_ARP (in 
    TCPIPConfig.h) turns this feature on or off.

Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  HI-TECH PICC-18 compilers are not supported in this release.  The supplied 
    HI-TECH PICC-18 MPLAB projects usually will not compile and/or link.
4.  ENC624J600 PSP modes 2, 4, 6, and 10 do not work at this time.  Some 
    Parallel Bit Bang modes may not work either.  Some minor firmware changes 
    are needed.
5.  TCPIP ENCX24J600 Demo App-C18.mcp project does not compile by default using 
    MPLAB C Compiler for PIC18 MCUs (C18) version 3.34.  There is not quite 
    enough program memory available on the PIC18F97J60 for the large number of 
    selected stack features to allow linking.  To get this project to compile, 
    turn on compiler optimizations or disable one of the modules in 
    TCPIPConfig.h (ex: comment out STACK_USE_DYNAMICDNS_CLIENT).




********
v5.10       29 July 2009
********
Changes:
1.  Added SSL capability to the Telnet server.  If STACK_USE_SSL_SERVER is 
    defined, the Telnet server will now listen on port 992 for SSL secured 
    connections.  If you do not have a telnets client, you can use an SSL proxy, 
    such as stunnel (http://www.stunnel.org/) to add SSL/TLS support to any 
    telnet client.
2.  Moved a number of string pointer tables in the HTTP.c, HTTP2.c, FTP.c, and 
    DynDNS.c files to allocate in ROM instead of RAM.  This reduces around 120 
    bytes of RAM usage in the HTTP2 server when compiled for the PIC18 or 
    PIC24/dsPIC platforms.  The gains are even greater on PIC32 platforms.
3.  Added redefinition of SPIRAM*(), SPIFlash*(), and XEEPROM*() functions so 
    that when compiled and used without proper HardwareProfile.h definitions, 
    a more descript linker error will be generated instead of a mysterious 
    symbol not found error.
4.  Added several new APIs:
    - ExtractURLFields() in Helpers.c.  This function provides an easy
      means of parsing an URL string and extracting the protocol, hostname, 
      port, file path, etc.  Currently, this function is commented out to save 
      code space as no stack modules require it.  However, it should work 
      correctly if you simply uncomment it (remove the #if 0...#endif around 
      it).
    - strnchr() in Helpers.c.  Finds the first occurrence of a character within 
      a string but limited to a maximum length before giving up.
    - TCPPeek() and TCPPeekArray() in TCP.c.  Reads from a TCP socket's RX 
      FIFO buffer without removing the data from the stream.
    - TCPClose() in TCP.c.  Disconnects a socket from the remote node (if 
      connected) and closes the socket handle, including for server type 
      sockets.  This function is identical to the TCPDisconnect() API except 
      for the handling of server sockets.  TCPDisconnect() returns server 
      sockets to the listning state and maintains the socket handle.  TCPClose() 
      closes the socket and frees all associated resources, invalidating the 
      socket handle.
5.  Updated the DHCP client module:
    - Modified so that it wouldn't attempt to transmit DHCP Discover packets 
      when the MAC layer reports no link (MACIsLinked() == FALSE).  This avoids 
      main() while(1) loop performance degredation when you unplug the Ethernet 
      cable or lose association to your access point.
    - Added capability of performing DHCP discovers and requests without 
      setting the BOOTP broadcast flag.  Now, the DHCP client module will start 
      up and attempt to obtain an IP address with the broadcast flag set, but 
      if it fails the next DHCP retry will attempt to obtain the IP address 
      with the broadcast flag cleared.  The flag will toggle back and fourth 
      between unicast mode and broadcast mode if no DHCP server responds.  This 
      feature improves compatibility with certain DHCP servers and WiFi access 
      points.
    - Added several new APIs including DHCPInit(), DHCPIsEnabled(), 
      DHCPStateChanged(), DHCPIsBound(), and DHCPIsServerDetected().
    - Removed the DHCPFlags DHCP_CLIENT_FLAGS global variable.  Use the above
      named APIs now to get equivalent functionality.
    - Removed the DHCPBindCount global variable.  To detect if the DHCP state 
      has changed, poll the new DHCPStateChanged() function.
    - Removed the DHCPReset() API.  To perform this operation, now call the 
      DHCPInit() API.  Use 0x00 for the vInterface parameter.
6.  Removed deprecated TickGetDiff() macro.  To get a tick difference, just 
    subtract the two values in-line.  This macro was removed because it promoted
    confusing code.  Ex: a-b is different from b-a.  However, it was not 
    contextually obvious which of the two was returned when TickGetDiff(a, b) 
    was called.
7.  Added PIC32MX460F512L USB and dsPIC33FJ256GP710 PIM support to the Explorer 
    16 hardware profile for the TCPIP WiFi Demo App and WiFi IPerf App projects.
8.  Added all files needed for SSL (assuming the crypto libraries are present) 
    to the TCPIP WiFi Demo App-C30 and TCPIP WiFi Demo App-C32 projects.
9.  Converted TCPIP Demo App, TCPIP WebVend App, Internet Radio App, and 
    Internet Bootloader App MPLAB Build Directory Policy to compile in the 
    project folder instead of the source folder.  This reduces the depedancies 
    on the MPLAB project include path and allows new projects to be created by 
    copying one of the pre-existing folders (ex: copy "TCPIP Demo App" to 
    "My App") without having problems including the wrong HardwareProfile.h and 
    TCPIPConfig.h files.
10. Changed EEPROM/SPI Flash AppConfig record valid flag from 0x60 to 0x61 in 
    the TCPIP WiFi Demo App and WiFi Iperf App projects.  This will force the 
    various EEPROM settings to get erased when switching between Ethernet and 
    WiFi projects.  This is done since the AppConfig structure changes when 
    using WiFi (SSID string is added).
11. The Wifi Iperf App and TCPIP WiFi Demo App projects have been optimized for 
    better performance.


Fixes:
1.  Fixed a TCPDisconnect() API bug in which the last few bytes of data (up to 
    the TCP socket's TX FIFO size less 532 bytes) was not transmitted and no 
    FIN was sent out if the TX FIFO was full of data when TCPDisconnect() 
    was called.  This problem could have only occurred for TCP sockets with a 
    large TX FIFO (>=532 bytes).  This problem could have been observed in 
    stack version 5.00's "TCPIP Demo App-C32 EXPLORER_16 32MX360F512L ENC624J600 
    PSP 9.hex" precompiled application, among others, if you connected to the 
    TCPPerformanceTest.c module and then attempted to simultaneously access the 
    web server.  The web server was returning data very slowly and failing to 
    send the last parts of each file requested by the browser.
2.  Eliminted a potential buffer overflow vulnerability from the 
    HTTPHeaderParseContentLength() function in HTTP2.c.  If an oversized or 
    malformed Content-Length header is sent from the web client, the function 
    will now gracefully fail by returning an HTTP 400 Bad Request error page.  
    Thanks go to Mark Philipp for identifying this error and suggesting a 
    solution.
3.  Fixed a TCPOpen() problem in which the stack would continuously flood the 
    network with nearly back-to-back ARP query packets if a client socket was 
    created that specified a non-reachable remote IP address (ex: local gateway 
    was offline, or for destinations on the same subnet, the actual remote node 
    was offline).  This problem would occur only after a few minutes (<10) had 
    passed since the PIC was last reset.  Thanks go to Sergey of DPS TELECOM for
    reporting this problem.
4.  Fixed linking problem with BigInt_helpers.S (PIC24/dsPIC only) when 
    targeting a PIC with more than 8KB of RAM.  The interface registers (_iA, 
    _xA, _iB, _xB, _iR, and _wC) are now forced into near RAM.
5.  Cleaned up some uninitialized variable warnings in SNMP.c.
6.  Fixed a sequence variable traversal bug in SNMP.c.
7.  Cleaned up a large number of unsigned integer to signed integer comparison 
    warnings produced by the MPLAB C Compiler for PIC18 MCUs (C18) version 
    3.32.  With earlier versions of this compiler, these warnings would only be 
    generated as messages, so they did not get displayed by default.
8.  Some ENCX24J600 parallel bit bang modes work now.  PSP Mode 5 indirect has 
    been tested.
9.  SSL client and server capabilities now work when using the ZeroG ZG2100M 
    WiFi interface.  In the 5.00 stack release, attempting to enable the 
    STACK_USE_SSL_CLIENT or STACK_USE_SSL_SERVER TCPIPConfig.h options with 
    this network controller would have resulted in an error trap.  If an LCD 
    was present, the LCD would display “encRdPtrRAWId = encWrPtrRAWId” when the 
    error occurred.
10. The WiFi Iperf App demo locked up when an invalid command was entered at 
    the serial port console.  This is now fixed. 
11. The WiFi Iperf App demo locked up when running with a PIC32 if iwconfig was 
    typed at the serial port console.  This is now fixed.
12. The Wifi Iperf App demo, when running on the PIC24 and PIC32, and compiled 
    with the –Os option (min code size optimization), did not work.  This is 
    now fixed.
13. Change a lot of BerkeleyAPI.c internals.  This may fix a number of BSD 
    API problems.
14. Fix a problem with SNMP variables being inaccessible with certain unique 
    PEN numbers.


Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  HI-TECH PICC-18 compilers are not supported in this release.  The supplied 
    HI-TECH PICC-18 MPLAB projects usually will not compile and/or link.
4.  ENC624J600 PSP modes 2, 4, 6, and 10 do not work at this time.  Some 
    Parallel Bit Bang modes may not work either.  Some minor firmware changes 
    are needed.
5.  SSL client code doesn't work with ENC424J600/624J600 devices.  The remote 
    server terminates the connection reporting a bad record MAC (Message 
    Authentication Code).  The SSL client does work with other controllers.



********
v5.00       27 April 2009
********
Changes:
1.  Added ZeroG ZG2100 802.11 WiFi controller support.  The new TCPIP WiFi Demo
    App and WiFi Iperf App projects have been added, which default to using this 
    controller.
2.  Added Microchip ENC424J600/624J600 10/100 Ethernet controller support.  
    Support for this controller is provided by the new ENCX24J600.c/.h files 
    which perform the same role as the ENC28J60.c/.h or ETH97J60.c/.h files.  
    Precompiled .hex files for the ENC624J600 controller require the use of the 
    new Fast 100Mbps Ethernet PICtail Plus daughter card (AC164132).  This 
    product is not available at the time of the 5.00 TCP/IP stack release.  
    However, it is anticipated to be available for purchase on 
    www.microchipdirect.com in CQ3 2009.
3.  Significantly updated the Internet Radio App project.  Previously, radio 
    stations were hard coded into program memory at compile time.  Now, a 
    dynamic Shoutcast directory client has been implemented which allows 
    retrieval of radio stations at run time, offering endless stations you can 
    tune into.  The web pages for the radio have also been updated to allow 
    control and status reporting of the board from a web browser.
4.  Update SNMP Server (Agent) module to support SNMPv2C.  The default Demo App 
    web pages now include an SNMP reconfiguration capability to set the read 
    and write community strings. 
5.  Added ICMPSendPingToHost() and ICMPSendPingToHostROM() APIs to ICMP (ping) 
    client module.  These two APIs are available only when STACK_USE_ICMP_CLIENT 
    and STACK_USE_DNS is defined in TCPIPConfig.h.  These functions allow 
    pinging of DNS hostnames directly without the need for the application to 
    convert the hostname to an IP address first by manually calling the DNS 
    client APIs.  With this addition, the PingDemo.c file was updated to ping 
    the hostname "ww1.microchip.com" instead of a static IP address.  Previously, 
    the PingDemo would stop working a couple of months after the stack was 
    released, due to the IP address of the www.microchip.com server dynamically 
    changing.  If the DNS module is not enabled, the ping demo will instead ping 
    the local gateway IP address instead of ww1.microchip.com.
6.  Updated TCPPerformanceTest.c code.  The previous version would generate 
    incorrect speed calculations at high data rates (ex: >1Mbyte/sec).
7.  Added multiple connection support to Telnet server example module.  To 
    allow multiple connections, define MAX_SIMULTANEOUS_CONNECTIONS in Telnet.c 
    greater than 1 and create an equal number of TCP_PURPOSE_TELNET type TCP 
    sockets in the TCPSocketInitializer[] definition in TCPIPConfig.h.
8.  Added more randomness to the local port selection when opening a client-mode 
    TCP socket.  This reduces the risk of reusing a previously used port number 
    if the user power cycles the device.
9.  Updated XEE* SPI EEPROM API functions.  Writes are no longer required to 
    start on an EEPROM page boundary, and writes can now be arbitrarily long 
    without having to call XEEEndWrite() at each page boundary.  Additionally, 
    the XEEWriteArray() API has been added, which performs a similar operation 
    to the SPIFlashWriteArray() API (but with no special erase cases to worry 
    about).
10. Decoupled AppConfig storage in external SPI EEPROM or SPI Flash option from 
    MPFS_USE_EEPROM and MPFS_USE_SPI_FLASH options.  MainDemo.c will now save 
    the AppConfig structure in external non-volatile memory, even if MPFS is 
    unused (no HTTP or SNMP server modules enabled) or MPFS is using internal 
    Flash program memory to store web pages/bib information.  This change also 
    allows the XEE*() and SPIFlash*() non-volatile read/write functions to be 
    available at all times (even if MPFS is unused), as long as the appropriate 
    hardware pinout definitions are present in HardwareProfile.h.  SPI Flash and 
    SPI EEPROM are no longer mutually exclusive with each other.  However, if 
    both are enabled simultaneously, AppConfig will be stored in the EEPROM, not 
    the SPI Flash.
11. Added required SSL files to TCPIP Demo App MPLAB projects.  SSL capabilities 
    can now be turned on directly via the STACK_USE_SSL_SERVER and 
    STACK_USE_SSL_CLIENT options in TCPIPConfig.h for these projects, assuming 
    appropriate crypto libraries are installed (SW300052 available from 
    https://www.microchipdirect.com/).  With this change, the historical "SSL 
    Demo App" folder has been removed.
13. Updated HardwareProfile.h files.  This includes the addition of PIC18 
    Explorer board support, removal of the PICDEM Z profile, changes to the 
    HI-TECH PICC-18 profiles for newer compilers, among other changes.
14. Added a TCP and UDP performance test measurements table to TCPIP Stack 
    Help (TCPIP Stack Help.chm).  Access this from the "Microchip TCP/IP Stack" 
    book, "Stack Performance" page.
15. Updated MPFSlib project (Microchip.MPFS.dll file) so that C18 and C32 output 
    from the MPFS2.exe utility is now identical for MPFS2 images.  The generated 
    .c file is now compatible with both C18 and C32 compilers simultaneously.  
    Previously, the images generated for C18 would compile successfully for C32 
    projects, but would potentially operate incorrectly when compiler 
    optimizations were turned on.  Images generated for C32 would compile 
    successfully and work on C18 projects, but the C18 compiler would take a very 
    long time to process the file each time you rebuilt your MPLAB project.  Now, 
    the image generated for C18 matches the image generated for C32 and it will 
    compile fast and work correctly on both platforms, even with compiler 
    optimizations turned on.
16. Added schematics and BOMs for the Ethernet PICtail, Ethernet PICtail Plus, 
    Fast 100Mbps Ethernet PICtail Plus, Internet Radio, PICDEM.net 2, and ZeroG 
    ZG2100M PICtail development boards to the "Microchip\TCPIP Stack\Demo Board 
    Files" folder.
   

Fixes:
1.  Fixed a denial of service vulnerability in the NBNSGetName() function of the 
    NBNS.c file.  Previously, if a deliberately malformed packet was received, 
    the PIC RAM could have become corrupted.  Thanks go to David Talmage for 
    finding this vulnerability.
2.  Fixed Timer1 interrupt flag clearing code on PIC32 products.  Previously, 
    the Tick.c module was clearing the interrupt flag in an unsafe manner which 
    could have corrupted other interrupt flags in the IFS0 register.  Thanks go 
    to Leon van Snippenberg working on the AVIX-RT RTOS for pointing this error 
    out on the Microchip forums.
3.  Fixed SNMP up-time variable.  Previously the CustomSNMPApp.c module would 
    respond with the number of Tick API ticks that elapsed, not the number of 
    10ms time slices that elapsed.  The SNMP standard uses 10ms as its time base.
4.  Fixed BigInt_helper.asm's _masBI() and _masBIROM() functions when the Br 
    parameter's length modulo 4 was equal to 1 or 2.  This bug previously caused 
    the BigIntMod() function to sometimes go into an endless calculation loop on 
    PIC18 products when using the SSL libraries and certain combinations of 
    modulus data and length were used.  Thanks go to Vasil Stoianov on the 
    Microchip Ethernet forum for running into this defect and reporting it.
5.  Fixed SSLSessionNew() so that it wouldn't "lose" SSL sessions after waiting a 
    few hours.  This would previously make it impossible to make new SSL 
    connections after a while, but then after a few more hours, the sessions 
    would become free again.  Thanks go to Jim Stephens for identifying this 
    issue and finding the solution.
6.  Fixed an SSL 2.0 antique client hello record length calculation bug occurring 
    when a received record was > 255 bytes.
7.  Added retransmission capability to SendNotification() function in 
    CustomSNMPApp.c.  Previously, if an SNMP trap were sent, but the initial ARP 
    query or response was lost on the network, the SendNotification() code would 
    have deadlocked, and suppressed all future transmission of SNMP traps.
8.  Fixed DNS client timeout if the DNS server is unable to be ARPed.  
    Previously, the DNS client would retry ARPing the DNS server indefinitely if 
    it was offline.  Now, the DNS client will correctly abort if too many 
    attempts to ARP the DNS server fail.  Thanks go to Phil "andersop" on the 
    Microchip Ethernet forum for identifying this error.
9.  Suppressed transmission of a TCP RST packet to an unknown IP or MAC address 
    if the TCPDisconnect() function was called on a client mode socket that was 
    not finished with ARP or DNS resolution yet.  Thanks go to Phil "andersop" on 
    the Microchip Ethernet forum for pointing this behavior out.
10. Fixed TCP socket from disconnecting if the remote receive window was zero and
    TCPFlush() was still called.  Thanks go to Bob Topper for identifying this 
    issue and suggesting a solution.
11. Fixed Tick.c module returning incorrect values when TickGet() or other API 
    was used with compiler optimizations turned on.  Wrong values were observed 
    when using MPLAB C Compiler for PIC24 MCUs and dsPIC DSCs version 3.12.
12. Fixed a number of SPI communications problems that could occur when compiler 
    optimizations were turned on.  The ENC28J60 was observed to not work 
    correctly on the dsPIC33FJ256GP710 processor when compiled with MPLAB C 
    Compiler for PIC24 MCUs and dsPIC DSCs version 3.12.
13. Fixed possible MPFS2 error when using an ASM30 .s image where MPFS_Start 
    would be read using the wrong PSVPAG setting.  You must rebuild your MPFS2 
    image file (ex: MPFSImg2.s) with this stack version's MPFS2.exe utility to 
    get this correction applied.


Known Problems:
1.  Telnet server module does not implement a lot of Telnet functions.  As a 
    result, it will likely not display correctly or work at all with some Telnet 
    clients.  The server was tested with the Microsoft telnet.exe utility which 
    is provided with Microsoft Windows.
2.  If the DHCP client and DHCP server are used at the same time and you connect 
    two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
    a crossover cable), a race condition can occur where both nodes will disable 
    their DHCP server and neither board will get a successful DHCP lease.  If 
    this unlikely scenario occurs, as a work around, simply reset one of the 
    boards to reenable it's DHCP server.
3.  HI-TECH PICC-18 compilers are not supported in this release.  The supplied 
    HI-TECH PICC-18 MPLAB projects usually will not compile and/or link.
4.  ENC624J600 PSP modes 2, 4, 6, and 10 do not work at this time.  Parallel Bit 
    Bang mode does not work either.  Some minor firmware changes are needed.



********
v4.55       10 November 2008
********
SSL Note: 
   RSA.c and ARCFOUR.c have not changed between the 4.50 and 4.55 releases.  
   Although the precompiled SSL Demo App .hex files will differ, you can 
   continue to use the previous TCP/IP Stack v4.50 Encryption Add-on with this 
   4.55 stack version.

Changes:
1. Added DNS client support for a secondary DNS server address.  Previously, the 
   AppConfig.SecondaryDNSServer setting was unused.  Now, the DNS client module 
   will automatically swap the AppConfig.PrimaryDNSServer and 
   AppConfig.SecondaryDNSServer values after any DNS query timeout (or ARP 
   timeout for the DNS server) and attempt the query with the alternative 
   server.  If AppConfig.SecondaryDNSServer is disabled by setting it to the IP 
   address 0.0.0.0, the DNS client will only use the AppConfig.PrimaryDNSServer 
   value and never swap the values.  With this change, the DHCP client was also 
   updated.  If the DHCP server does not specify a secondary DNS server, then 
   the DHCP client will now set the AppConfig.SecondaryDNSServer value to 
   0.0.0.0.  Previously, it would change the AppConfig.SecondaryDNSServer 
   setting only if the remote DHCP server offered a secondary DNS server.
   

Fixes:
1. Updated Internet Bootloader App project to correctly detect if the 
   configuration bits are being changed or not.  Previously, the bootloader 
   always thought the configuration bits were being changed and thus had to 
   always erase the last Flash page (largest memory address) twice for each 
   firmware update.  This did not cause any functional problems or 
   specification violations, but it would decrease the effective Flash 
   endurance of the last page.
2. Fixed a TCP socket memory corruption bug that would occur if 
   TCPGetRemoteInfo() API was called twice with different socket handles 
   without an intermediate call to any other TCP API that takes a 
   TCP_SOCKET input.  Thanks go to Bob Topper for identifying this problem and 
   suggesting a solution.
3. Fixed the UDPIsGetReady() function so that it returns the number of bytes 
   remaining in the packet based on the current read location.  This is the 
   same behavior as stack versions 4.18 and earlier.  In stack versions 4.50 
   and 4.51, the UDPIsGetReady() function would always return the total number 
   of bytes in the current packet, regardless of how many bytes the read 
   pointer had been advanced through the UDPGet() and UDPGetArray() functions.  
   Thanks go to Bob Topper for identifying this problem and suggesting a 
   solution.
4. Fixed demo admin web page in TCPIP Demo App project so that the last byte of 
   the MAC address can be changed, independent of the format it was entered by 
   the user.
5. Fixed a buffer overflow bug that would occur when using the SSL server during 
   hashing of the server certificate for the initial handshake.  This error 
   previously caused several bytes of random variables elsewhere in the project 
   to get overwritten for each SSL connection.
6. BSD sockets API was updated to fix some issues.
7. LCDBlocking.c was updated to relax start up timing.  This timing fix is 
   specifically needed to support Explorer 16 boards with a Truly TSB1G7000 
   display (Novatek NT7603H controller).
8. Removed four uses of Arial Black font in MPFS2.exe utility.  On some rare PC 
   configurations, the use of this font caused the executable to not run.


Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
3. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
4. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate TCP_ETH_RAM_SIZE or MAX_HTTP_CONNECTIONS.
5. HI-TECH PICC-18 STD 9.51PL1 cannot compile DynDNS.c.  It raises an 
   "inconsistent type" error while trying to perform a ROM pointer to integer 
   cast.  The older 9.50PL3 compiler release is required to compile this file.
6. HI-TECH PICC-18 STD 9.50PL3 does not initialize several static variables 
   correctly on reset.  This behavior breaks many stack modules in the 
   TCPIP Demo App and TCPIP WebVend App projects.  Additionally, string 
   printing functions do not work correctly, so the supplied 
   "TCPIP Demo App-HITECHPICC18 PICDEMNET2 18F97J60.hex" and "TCPIP WebVend 
   App-HITECHPICC18 PICDEMNET2 18F97J60.hex" files may not correctly print the 
   board's DHCP assigned IP address on the board's LCD (if present) and UART.  To 
   avoid these severe problems, use the Microchip MPLAB C Compiler for PIC18 MCUs.  
   A free student edition can be downloaded from http://www.microchip.com/c18.



********
v4.51       24 July 2008
********
IMPORTANT NOTE: You must use MPLAB 8.10 or higher to successfully open the 
   MPLAB projects.

SSL Note: 
   RSA.c and ARCFOUR.c have not changed between the 4.50 and 4.51 releases.  
   Although the precompiled SSL Demo App .hex files will differ, you can 
   continue to use the previous TCP/IP Stack v4.50 Encryption Add-on with this 
   4.51 stack version.

Changes:
   None.  This release includes bug fixes only.  It is very important that 
   applications using the ENC28J60 get fix item 7, below.
   

Fixes:
1. TCPOpen() was previously failing if you used it to start a connection with a 
   remote hostname, but the DNS module failed to resolve the remote address on 
   the first try.  This, for example, would occur if you powered up your board 
   and tried to connect to a remote server before the Ethernet cable was 
   attached.  Once the Ethernet cable was attached, the socket would attempt to 
   resolve and connect to a garbage address.  The Internet Radio application 
   would sometimes not begin playing the default station upon power up because 
   of this problem.
2. Set SEQ.ACK = 0 for outbound TCP SYN packets.  This fixes a connection 
   compatibility problem with certain paranoid TCP/IP stacks that would validate 
   this field even though the ACK flag was clear.  This problem would previously 
   cause the Microchip TCP/IP stack to be unable to connect client-mode TCP 
   sockets to certain rare servers/services.  Thanks go to Jean LE TUTOUR for 
   finding one of these problem servers.
3. MPFSOpen() and MPFSOpenROM() for MPFS2 could leak a file handle if a name 
   hash matched but no complete file name did.  This has been corrected to 
   prevent potential DOS attacks on the HTTP2 web server.  Thanks to David Tan 
   on the Microchip Ethernet formus for identifying this issue.
4. Fixed a bug in MPFS2.1 that caused compile errors when MPFS Classic images
   were generated for ASM30 containing files whose length was either zero or
   a multiple of 12.
5. Fixed an issue in HTTPPostConfig() that caused it to ignore the flag that
   was set when invalid IP address input was detected.  This issue only affects 
   the example configuration page and only exists in v4.50 (prior versions 
   functioned correctly).  Also corrected an issue where user input could 
   potentially overflow into part of the shadow AppConfig in the same function.
   Thanks to prinz3nroll3 on the Microchip Ethernet forums for identifying 
   both of these issues.
6. Implemented Explorer 16 development board 5V LCD errata workaround to 
   LCDBlocking.c.  This corrects the A/D converter from returning erratic 
   readings on certain Explorer 16 boards.  LCD I/O pins are now continuously 
   driven by the microcontroller instead of going high impedance when idle.
7. Fixed a critical ENC28J60 revision B7 errata workaround problem in the 
   ENC28J60.c, MACFlush() function.  Previously, the code was checking for an 
   EREVID register value of 0x07 for silicon revision B7.  This was incorrect.  
   Silicon revision B7 actually has an EREVID value of 0x06.  Note that this 
   problem was caused by an incorrect EREVID value published in DS80349A, the B7 
   silicon errata documentation.  Make sure to use DS80349B or later.


Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
3. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
4. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate TCP_ETH_RAM_SIZE or MAX_HTTP_CONNECTIONS.
5. HI-TECH PICC-18 STD 9.51PL1 cannot compile DynDNS.c.  It raises an 
   "inconsistent type" error while trying to perform a ROM pointer to integer 
   cast.  The older 9.50PL3 compiler release is required to compile this file.
6. HI-TECH PICC-18 STD 9.50PL3 does not initialize several static variables 
   correctly on reset.  This behavior breaks many stack modules in the 
   TCPIP Demo App and TCPIP WebVend App projects.  Additionally, string 
   printing functions do not work correctly, so the supplied 
   "TCPIP Demo App-HITECHPICC18 PICDEMNET2 18F97J60.hex" and "TCPIP WebVend 
   App-HITECHPICC18 PICDEMNET2 18F97J60.hex" files may not correctly print the 
   board's DHCP assigned IP address on the board's LCD (if present) and UART.  To 
   avoid these severe problems, use the Microchip MPLAB C Compiler for PIC18 MCUs.  
   A free student edition can be downloaded from http://www.microchip.com/c18.



********
v4.50       02 June 2008
********
IMPORTANT NOTE: You must use MPLAB 8.10 or higher to successfully open the 
   MPLAB projects.  Also, ensure that the latest C compiler is used.  This 
   release was tested against MPLAB C Compiler for PIC18 MCUs version 3.20, 
   MPLAB C Compiler for PIC24 MCUs and dsPIC DSCs version 3.10, MPLAB C 
   Compiler for PIC32 MCUs version 1.01, and HI-TECH PICC-18 version 
   9.50PL3 (STD).  Earlier compilers may not be able to compile this TCP/IP 
   stack release.


Changes:
1. Added SSL 3.0 client capabilities, including SMTP over SSL.  The SSL
   modules supports up to 1024-bit RSA handshakes and 128-bit ARCFOUR 
   bulk encryption.  This can be demonstrated using the SMTP client.  SSL
   server support is functional, but a key generation utility is not yet 
   provided and support over HTTPS is not yet reliable with all browsers.
   IMPORTANT: Encryption software is covered by US Export Control law, so
   it is not directly downloadable from the Microchip website.  To use the 
   encryption modules, you must order SW300052 from microchipDIRECT 
   [ https://www.microchipdirect.com/ ] and install the required libraries.
2. Added Berkeley Sockets Distribution (BSD) API translation layer.  You can 
   now call the well know Berkeley APIs instead of or in addition to the 
   Microchip specific APIs.  To use this new functionality, define 
   STACK_USE_BERKELEY_API and configure BSD_SOCKET_COUNT in TCPIPConfig.h.  
   Three new source code demos are provided to demonstrate this API: 
   BerkeleyTCPClientDemo.c, BerkeleyTCPServerDemo.c, and 
   BerkeleyUDPClientDemo.c.  The TCP client demo is identical to the 
   GenericTCPClient.c demo, but implemented using Berkeley Sockets.  The UDP 
   client demo is similarly identical to the SNTP.c client.  The TCP server 
   demo listens on TCP port 9764 and will echo any traffic received back to the 
   sender.  It allows up to 3 simultaneous connections when there are an 
   adequate number of sockets defined in the TCPSocketInitializer[] array in 
   TCPIPConfig.h.
3. Added support for Dynamic DNS services.  See the Dynamic DNS Client module in 
   the TCP/IP Stack Help for details.  Presently, dyndns.org, dyndns.com, 
   no-ip.com, and dns-o-matic.com are supported.
4. Added the Microchip TCP/IP Configuration Wizard to the Utilities folder, 
   facilitating easier configuration of the TCP/IP Stack through a 
   graphical application.
5. Restructured TCPIPConfig.h to remove rule-enforcement logic, placing the 
   removed sections in TCPIP.h.  Many other project structure changes were also 
   made to clean up the general distribution appearance.
6. Increased DHCP Server default lease duration to 60 seconds instead of 15 
   seconds.  Some computers were losing their IP lease before performing a renew 
   operation with only a 15 second lease.
7. Removed CLOCK_FREQ, INSTR_FREQ, and PERIPHERAL_FREQ macro definitions.  
   GetSystemClock(), GetInstructionClock(), and GetPeripheralClock() now return 
   these respective values.  This change was made for compatibility with other 
   Microchip software libraries.
8. Added TCP Fast Retransmission capability.  Whenever three duplicate ACK 
   packets arrive, the stack will now immediately perform a retransmit 
   operation.  This greatly improves recovery latency whenever the network 
   loses a packet for applications that stream TX data using TCP.
9. Improved TCP Keep Alive mechanism to automatically close TCP sockets which 
   do not receive any keep-alive responses for TCP_MAX_UNACKED_KEEP_ALIVES 
   (default 6) times.  This means that, by default, any connection that 
   catastrophically breaks without notifying us (ex: user unplugs cable, 
   Internet connection goes down, etc.) will time out and automatically close 
   after 60 seconds (TCP_MAX_UNACKED_KEEP_ALIVES * TCP_KEEP_ALIVE_TIMEOUT).  
   Server oriented sockets will return to the listening state.  Client oriented 
   sockets will close, but the TCP_SOCKET handle will continue to remain valid 
   until the application calls TCPDisconnect().  Applications can check if the 
   socket became disconnected and reset by calling TCPWasReset() or 
   TCPIsConnected().  Note that this keep alive implementation will only close 
   sockets that are broken (remote node is not responding to TCP requests).  It
   will not close or otherwise interfere with idle connections in which the 
   application is not transmitting or receiving data and wishes to keep the 
   connection open.
10.Added a TCP RX SYN queue of depth TCP_SYN_QUEUE_MAX_ENTRIES (default 3).  
   This queue automatically saves incoming SYN packets destined for a local 
   server port which is already connected to a different client.  When the 
   client disconnects, the SYN data is pulled out of the queue and the socket 
   immediately attempts to connect to the next client.  This improves connect 
   time performance since the remote client no longer has to retransmit the 
   SYN request if it was unserviceable the first time around.  This is most 
   apparent with the HTTP/HTTP2 servers which previously performed poorly 
   with certain modern web browsers which attempt to open many simultaneous 
   connections to the web server, such as Mozilla Firefox 3 beta 5 and Apple 
   Safari 3.1.  Entries in the queue automatically time out after 
   TCP_SYN_QUEUE_TIMEOUT (default 3 seconds) so as to prevent the queue from 
   filling up permanently if several connection requests arrive for a service 
   that is in use and will not be available for an extended period.
11.Modified the structure of the MPFS2 FAT (now known as MPFS2.1) to include 
   name hashes first.  This speeds up opening files by 25%, and makes opening 
   index files nearly instant.
12.Updated the MPFS2 Utility.  MPFS2.1 now supports the new FAT structure and 
   provides a cleaner interface.  It also writes images to disk as they are 
   created, which eliminates the IndexOutOfBounds exceptions some users had 
   reported.  Finally, uploads are now truly multi-threaded.
13.Source code to the MPFS2.exe PC utility is now released.  Find it in the 
   Microchip Solutions\Microchip\TCPIP Stack\Utilities\Source\MPFS21 folder.  This 
   project is designed to compile with Microsoft Visual C# 2008 Express Edition.
14.Added support for SST25VFxxxB serial flash parts in 2, 4, 8, 16, and 32Mbit
   densities.  These parts can be used to replace EEPROMs for storing MPFS
   images (both versions) and custom data.
15.Added HTTPReadPostName, HTTPReadPostValue, and HTTPReadPostPair functions to 
   facilitate easier processing of data arriving via POST.
16.Split HTTPAuthenticate API into separate functions: HTTPNeedsAuth and 
   HTTPCheckAuth.  This function was already split internally, and didn't 
   make sense as a single API.
17.Updated DHCP client to close its UDP socket when idle (bound state) to save 
   a small amount of resources.
18.Removed LED_IO macro from all hardware profiles because it is not suitable 
   for use on certain hardware platforms that have non-contiguous LEDs or 
   reversed bit ordering.  Use the new LED_GET() and LED_PUT(val) macros to read 
   and write to all of the LEDs at once.
19.Added Ethernet Hash Table Calculator.exe to the Utilities folder and start menu.
   This tool will calculate the correct bit that you must set in the EHT0-EHT7 
   registers on the ENC28J60 and PIC18F97J60 family devices for using the Hash 
   Table RX filter.  This is useful only for fixed MAC addresses known at design 
   time.  For addresses that are known at run time, use the SetRXHashTableEntry() 
   function in the ENC28J60.c or ETH97J60.c files to set the correct EHT0-EHT7 bit.
   

Fixes:
1. Fixed a buffer overflow data corruption issue in the FTP module that arises 
   when too many parameters were passed on the command line.
2. Moved TCPWasReset checking in HTTP2 to execute for every socket on every
   loop.  Previously, it would only execute when a socket reconnected, which 
   caused the RX buffer to not resize until after data was received.  Some 
   platforms (notably FF2 on Ubuntu) would stall if the initial advertised RX 
   window was too small, and this change corrects that issue.
3. Updated SendSystemReset() and MACInit() initialization routine in ENC28J60.c.  
   Previously, if the ENC28J60 was placed into sleep mode by calling 
   MACPowerDown(), the SendSystemReset() command would not work anymore.  This 
   would leave the ENC28J60 in power down if the host PIC was ever reset.  
   SendSystemReset() should work for all conditions with this update.
   Thanks go to Rob Haverkort on the Microchip Ethernet forum for identifying 
   this problem.
4. Fixed an alignment bug in HTTP2 that caused redirects to fail when the MPFS2
   image was stored in Flash program memory.  Thanks to Todd Boaz on the
   Microchip Ethernet forum for identifying this bug, and Chen Qu for posting
   a solution.
5. Fixed SNTP client from losing accuracy if you called SNTPGetUTCSeconds() 
   10s of thousands of times since the last server synchronization.  Thanks go to
   "pic123" on the Microchip Ethernet forum for noticing this error.
6. Fixed a TickGet*() API problem where the returned tick value could be off by 64K 
   ticks occasionally on PIC24, dsPIC30/33, and PIC32 processors.  This bug was 
   previously fixed in stack versions 4.13 and 4.16, but it was unintentionally 
   recreated in 4.18 due to PIC32 changes.
7. Fixed UART2TCPBridge module from failing to connect to a remote server when 
   USE_REMOTE_TCP_SERVER was defined.
8. Fixed an issue that prevented SNMP SETs on 16 and 32 bit parts when using
   MPFS2.  Thanks go to Milena K on the Microchip Ethernet forum for identifying
   this problem.
9. Fixed a rare buffer corruption issue that could occur with UDP if TCP was also 
   enabled.
10.Fixed a Tick rollover error in HTTP2.  Thanks go to Paul Bixel on the Microchip
   Ethernet forum for identifying this problem.
11.Fixed an MPFS2 bug in which an excessive value to MPFS_SEEK_REWIND may have 
   failed to return an error.  Thanks go to Paul Bixel on the Microchip Ethernet 
   forum for identifying this problem as well.
12.SMTP Client now sends EHLO when using authentication.  Previously, the HELO
   command was used, even with authentication enabled.  Using HELO with 
   authentication creates incompatibilities with certain SMTP servers.
13.Improved Internet Bootloader robustness by retransmitting ACKs in response to 
   data retransmissions by the remote sending node.  Previously, if an ACK packet 
   was lost before reaching the sending node, the TFTP upload would fail and need 
   to be restarted.  Thanks go to "coolvibe" Dave Collier on the Microchip Ethernet
   forum for identifying this behavior.
14.Fixed TFTP Internet Bootloader from not being accessible from Linux TFTP clients 
   which were setting the IP header "Don't Fragment" flag bit.
15.Changed TCP so that unsent data that is automatically flushed by the 
   TCP_AUTO_TRANSMIT_TIMEOUT_VAL timer includes the PSH flag.  This improves GUI 
   responsiveness for certain applications which rely on this automatic flush 
   feature, such as the UART2TCPBridge module.
16.Fixed TCP socket loss issue which could occur if the TCP TX FIFO size was 
   greater than 536 bytes (TCP_MAX_SEG_SIZE).  Before the fix, the socket 
   would have gotten tied up indefinitely performing retransmissions every 1.0 
   seconds without detecting that the remote node was disconnected.
17.Fixed TCP socket hang issue that would occur if the PIC sent out a FIN and the 
   remote node never responded with a corresponding FIN.  The socket would have 
   gotten stuck indefinitely in the TCP_FIN_WAIT_2 state.  Thanks go to Mr. Kyle 
   Strickland with AW North Carolina for identifying this bug.
18.Fixed UDPSetRxBuffer() function from not working if it was called before having 
   called UDPGet() or UDPGetArray() at least once.
19.Fixed an offset error of +2 milliseconds being returned from 
   TickConvertToMilliseconds().  Thanks go to Andrés ("saturn") on the Microchip 
   Ethernet forum for finding this error.  Note that due to integer truncation 
   during division, this function can be off by 0.2% or so, depending on the value 
   returned by GetPeripheralClock().
20.Updated DelayMs() macro for MPLAB C Compiler for PIC18s to work correctly 
   when a large parameter was given.  You should now be able to delay between 
   0 and 65535 milliseconds across all supported compilers without ending up 
   with an unexpectedly short delay.


Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
3. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
4. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate TCP_ETH_RAM_SIZE or MAX_HTTP_CONNECTIONS.
5. HI-TECH PICC-18 STD 9.51PL1 cannot compile DynDNS.c.  It raises an 
   "inconsistent type" error while trying to perform a ROM pointer to integer 
   cast.  The older 9.50PL3 compiler release is required to compile this file.
6. HI-TECH PICC-18 STD 9.50PL3 does not initialize several static variables 
   correctly on reset.  This behavior breaks many stack modules in the 
   TCPIP Demo App and TCPIP WebVend App projects.  Additionally, string 
   printing functions do not work correctly, so the supplied 
   "TCPIP Demo App-HITECHPICC18 PICDEMNET2 18F97J60.hex" and "TCPIP WebVend 
   App-HITECHPICC18 PICDEMNET2 18F97J60.hex" files may not correctly print the 
   board's DHCP assigned IP address on the board's LCD (if present) and UART.  To 
   avoid these severe problems, use the Microchip MPLAB C Compiler for PIC18 MCUs.  
   A free student edition can be downloaded from http://www.microchip.com/c18.



********
v4.18       28 November 2007
********
Changes:
1. Added C32 and PIC32MX support.  Some things were cleaned up in the process.
2. Removed linker scripts from C30 MPLAB projects.  MPLAB IDE 8.00 
   can automatically select the correct linker script for 16-bit and 32-bit 
   products.
3. Updated TCPPerformanceTest.c module.  Now it automatically calculates the TX 
   throughput and displays it for you.  Also, there is now an RX throughput 
   testing mode, which listens on a separate TCP socket (port 9763) when a TCP 
   socket of type TCP_PURPOSE_TCP_PERFORMANCE_RX is allocated in TCPIPConfig.h.  
   The RX socket is by default not enabled to save memory, so you must create a 
   TCP_PURPOSE_TCP_PERFORMANCE_RX socket in TCPIPConfig.h and ensure that enough 
   memory is allocated to accommodate it to test the RX performance test.  When 
   connected to port 9763, send a large amount of data and the PIC 
   microcontroller will send back a count of how many bytes were received per 
   second.  
4. UDPPerformanceTest.c module now transmits 1024 packets on start up and then 
   stops to prevent continually broadcast flooding your network.  To transmit 
   more packets after 1024 is reached, hold down BUTTON3 (left-most button on 
   most boards).
5. Significantly improved the speed of the MD5 and SHA-1 functions.  Gains for 
   the 8-bit compilers were 50-75%, while 16-bit parts saw more modest
   improvements (~10%).
6. Reimplemented TCP_CLOSE_WAIT TCP state ("CLOSE WAIT" in RFC793).  Now, TCP 
   sockets that receive a FIN from the remote node will hold off transmitting 
   a FIN back to the remote node until the TCP_CLOSE_WAIT_TIMEOUT (defined at 
   the top of TCP.c) elapses or immediately when the application calls the 
   TCPDisconnect() function.  This makes it possible for the application to 
   transmit a response back to the remote node before the socket becomes closed 
   on our end.  Similarly, it simplifies application usage of the last RX bytes 
   received as these bytes are now assured to still be in the RX FIFO for at 
   least TCP_CLOSE_WAIT_TIMEOUT seconds.  TCP_CLOSE_WAIT_TIMEOUT defaults to 
   200ms in this stack version.
7. Pushed the SNTP requery on failure timeout up some.  It was ~14 seconds and 
   is now ~20 seconds.
8. Added TFTPOpenROMFile() API to complement TFTPOpenFile() when using PIC18 
   products.
9. Added a fourth parameter to newAJAXCommand() in mchp.js, allowing data to be
   POSTed along with the AJAX request.
10.Deprecated the TCP Loopback functions, which includes TCPOpenLoopback, 
   TCPCloseLoopback, TCPIsLoopback, TCPInject, and TCPSteal.  These functions
   were added in 4.10 for future SSL support, but have since become 
   unnecessary.  They are of limited usefulness, and so are being removed to save
   code space.  The functions are still available in this version, but will 
   be removed in the next release.
11.Added SMTPClient.ServerPort field to the SMTP API.  This allows the remote 
   server port number to be specified dynamically at run time instead of being 
   hard coded to the SMTP_PORT value defined at the top of SMTP.c.  SMTP_PORT is 
   now only a default.
12.Added web interface to the SMTP module in the TCPIP Demo App applications.  
   You can now configure the SMTP module and send emails directly from within 
   your web browser.  The HTTPPostEmail() function in CustomHTTPApp.c also 
   demonstrates how to send MIME encoded attachments in emails.  The default demo 
   will send button states, LED states, and the current potentiometer reading as 
   a CSV file attached to the email.
13.Changed SMTPDemo() in MainDemo.c to trigger on BUTTON2 and BUTTON3 
   simultaneously held down instead of BUTTON0 only.

Fixes:
1. Fixed an ENC28J60.c MACGetArray() bug which would overwrite one byte of memory 
   at address 0xFFFFFFFF if you provided NULL for the destination address pointer.
2. Fixed an MPFS2.c MPFSGet() bug which would overwrite memory address 0x00000000 
   if a NULL pointer was provided as the destination.
3. Fixed a bug in the HTTP2 server accessing incorrect sockets if an inadequate 
   number of sockets were available on POR.
4. Fixed Internet Bootloader project from failing with a timeout if an ARP packet 
   arrived during the Erase/Write operation.
5. Fixed DHCP client RFC non-compliance where it would send the ciaddr field in 
   the initial SELECTING state.  Also, in the RENEWING state, the Requested IP 
   Address option was being sent, which is illegal.  These changes may fix 
   compatibility problems with certain DHCP servers.
6. Fixed TFTP Client's TFTPCloseFile() function from sending data using a wrong 
   UDP socket if StackTsk() was called after TFTPIsFileOpened() was last called.
7. Added two zero bytes to the ICMP echo request payload to improve compatibility 
   with some buggy NAT routers.

Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
3. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
4. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate TCP_ETH_RAM_SIZE or MAX_HTTP_CONNECTIONS.



********
v4.16       06 November 2007
********
Changes:
1. Added Internet Radio application.  This is a TCP client application which 
   downloads streaming MP3 audio from a Shoutcast server and then plays it back to 
   stereo earphones via a VLSI VS1011 audio decoder.
2. Added SPIRAM.c module.  This module is intended for interfacing to an AMI 
   Semiconductor N256S0830HDA SPI RAM chip.  The TCP module can now interface 
   directly to this SPIRAM module to store TCP socket FIFO buffers and other TCB 
   data in the external RAM.
3. Added TCP_OPTIMIZE_FOR_SIZE compile time configuration macro to TCP.c file.  When 
   optimizing for small code size, the TCP module ROM footprint shrinks up to 6KB, 
   but performance may slow down on some processors (namely PIC18s, where the 
   penalty is approximately 15%).
4. Added USE_EEPROM_25LC1024 compile time configuration macro to TCPIPConfig.h.  
   Enable this definition if you are storing your MPFS[2] on a 1Mbit 25LC1024 or 
   similar EEPROM device that uses 24-bit addressing and a 256 byte write page size.
5. Changed LCDBlocking.c module initialization code.  It should now be possible to 
   use 4-bit mode on certain "unusual" LCD controllers, like the Samsung S6A0032.  
   Most PICDEM.net 2 and Explorer 16 boards use an LCD with this controller.
6. SNTP client now attempts to requery the SNTP server about every 14 seconds if the 
   last query attempt fails.  This allows the internal time value to become valid 
   quickly should the board be powered up before an Ethernet cable is attached or if 
   the DHCP client doesn't obtain an IP address quickly enough.  Previously, it would 
   take up to 10 minutes after plugging the Ethernet cable in to get a correct time 
   value from the SNTP server.
7. Added UDP_USE_TX_CHECKSUM compile time configuration macro to TCPIPConfig.h.  
   When enabled, all UDP packets will have a correct UDP checksum computed and 
   inserted into the UDP header of outbound packets.  If you do not define this 
   macro, the UDP checksum will be disabled (left as 0x0000), which is how previous 
   stack versions operated.  Note that enabling checksum generation cuts your 
   maximum UDP TX throughput by nearly half due to the required computations.
8. Substantially changed TCP socket RX and TX FIFO allocation.  Now, sockets can be 
   stored either in Ethernet RAM, PIC RAM, or external (SPI) RAM.  Previously, 
   sockets could only be allocated in Ethernet RAM, which was not scalable.
9. Added TCPOpen() API function.  This replaces TCPListen() and TCPConnect().  
   TCPOpen() supports a large number of options that will make the creation of 
   client mode sockets much easier.  You can specify the remote node as a hostname 
   that needs DNS and ARP resolution, an IP address that only needs ARP resolution, 
   or legacy NODE_INFO pointer for direct compatibility with the previous 
   TCPListen() and TCPConnect() APIs.  TCPOpen() also supports a socket type 
   parameter which will allow you to use the new TCP socket RAM allocation system.
10.Added TCP Keep Alive mechanism defined by RFC 1122 section 4.2.3.6 to the TCP 
   module.  This helps automatically detect lost connections.  If the remote node 
   sends back an RST, this immediately closes the lost connection on our end.  
   Currently, no action is taken if the keep alive gets no response.  Note that this 
   feature deviates from the standard by defaulting to only 10 seconds instead of 
   over 2 hours.  Also deviating from the standard, this feature is enabled by 
   default.  To disable it, undefine TCP_KEEP_ALIVE_TIMEOUT at the top of TCP.c.
11.Moved TCPPerformanceTest.c module from default port 12345 to 9762.
12.Moved UDPPerformanceTest.c module from default port 12345 to 9, the "discard" 
   protocol port.

Fixes:
1. The DHCP client now specifically requests the previous IP address when a DHCP 
   renewal occurs.
2. The SNTP client now correctly maintains time when repetitively calling 
   SNTPGetUTCSeconds() between an NTP requery event.  Thanks go to Rob Haverkort on 
   the Microchip Ethernet forum for noticing the time value incrementing far faster 
   than it should have.
3. TCP module will not transmit a bunch of unnecessary duplicate ACK packets when 
   data is ready to be transmitted but the remote RX window is zero.  This previously 
   didn't cause anything to break, but would waste CPU time and bandwidth sometimes.
4. TCP sockets will no longer automatically close if the remote RX window stays zero 
   for several seconds.
5. Fixed TFTP Internet Bootloader project from corrupting the configuration fuses.  
   Previously, this would result in the Watchdog timer being enabled and causing an 
   unintentional reboot every few minutes with the demo TCP/IP stack.

Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. TFTPc module has not been tested with this version.
3. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
4. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
5. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate MAX_TCP_SOCKETS, TCP_TX_FIFO_SIZE, TCP_RX_FIFO_SIZE, or 
   MAX_HTTP_CONNECTIONS.



********
v4.13       02 October 2007
********
Changes:
1. Added command line support to the MPFS2.exe tool.  You can now generate MPFS 
   output files using batch scripts or other console applications.
2. Added dynamic variable parameter capabilities to the MPFS2 utility.  To use, add 
   the parameters you wish to pass to the end of the dynamic variable.  All 
   parameters are passed as WORD values.  (ex: ~myArray(2,5)~ )
3. Added TCPWasReset() API to allow the application layer to be notified if an 
   underlying socket reset has occurred (ex: remote node disconnects, cable is 
   disconnected and times out, user calls TCPDisconnect(), etc.).  The reset state is 
   latching, which allows the application layer to detect if a remote node disconnects 
   and a new connection occurs on the same socket before the application can detect 
   the original disconnection through the TCPIsConnected() API.
4. Added a counter to the UDPPerformanceTest module and made it supress transmission 
   if an Ethernet link is not present.
5. Added TCPIP WebVend App example application to the main stack distribution.  This 
   corresponds to three new Microchip Webinars being published on the HTTP2 server 
   usage topic.

Fixes:
1. Fixed MPFS2.exe PC utility from crashing if you attempt to generate an MPFS 
   classic .bin/.c/.s output file.
2. Fixed RCONbits definition for HPC_EXPLORER hardware profile when using the HI TECH 
   PICC-18 compiler.
3. Fixed a MPFSGetFilename() bug when using C30 and MPFS2 images stored in program 
   memory.  Thanks to Billy Walton on the Microchip Ethernet forum for identifying
   this issue.
4. Fixed a TCP RX FIFO corruption problem which would occur if the remote node sent 
   more data than could fit in our RX FIFO in a single packet.  The GeneticTCPClient.c 
   module was subject to experiencing this problem when connected to www.google.com's 
   servers.
5. Fixed a DHCP client UDP socket leak if you called DHCPDisable() after the DHCP 
   client had already obtained a UDP socket.  Thanks go to Matthew Kendall on the 
   Microchip Ethernet forum for identifying this problem.
6. Fixed a SNMP Server module bug testing a string length (with respect to 
   SNMP_COMMUNITY_MAX_LEN) being off by one, resulting in possible memory corruption.  
   Thanks go to Matthew Kendall on the Microchip Ethernet forum for identifying this 
   problem.
7. Cleaned up some C30 compiler warnings related to macro definitions with inadequate 
   parenthesis in them.
8. Fixed HTTP2 module sometimes returning a 501 error instead of a correct web page 
   when being bombarded with new connection requests.
9. Fixed a TickGet*() API problem where the returned tick value could be off by 64K 
   ticks occasionally on PIC24 and dsPIC processors.
10.Fixed SMTP client module failing to send email when attempting to send an email 
   with a `CC' or `BCC' field that was in ROM while the `To' field was in RAM or visa 
   versa.
11.Fixed TCP module sending an incorrect sequence number in RST packets sent when in 
   the TCP_SYN_SENT state and an invalid segment arrives.  In prior stack versions, 
   some TCP client applications might take a very long time to recover in the event 
   of a power failure, reset, and subsequent reconnect to a remote server that still 
   thinks the old connection is still active.  With this fix, reconnections should be 
   possible almost immediately after a power failure because the correct RST packet 
   will cause the old connection to get closed right away.
12.Fixed a TCP socket leak problem that would occur over if the local PIC called 
   TCPDisconnect() and the remote node didn't send us a correct FIN response.  
   Sockets could previously get lost in the TCP_FIN_WAIT_2 state and wouldn't 
   recover unless the application called TCPDisconnect() a second time with the same 
   socket handle.

Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. TFTPc module has not been tested with this version.
3. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
4. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
5. HI-TECH PICC-18 projects will not correctly set the processor configuration fuses 
   through code using the __CONFIG() macro.  Ensure that the configuration fuses are 
   manually set correctly via the MPLAB IDE Configuration Bits dialog.  This problem 
   has been observed with compiler version 9.50PL3.
6. MAC.h RXSIZE precompiler test for proper range doesn't work.  This is not a 
   functional problem, just a compile-time configuration test.  Ensure that you don't 
   over allocate MAX_TCP_SOCKETS, TCP_TX_FIFO_SIZE, TCP_RX_FIFO_SIZE, or 
   MAX_HTTP_CONNECTIONS.
7. GenericTCPClient example of downloading a web page from www.google.com is extremely 
   slow.  The default TCP socket has too little RX space to accept a full packet sent 
   from Google's servers, so the remote server must retransmit a lot of data, slowing 
   the transfer down a lot.  Making TCP_RX_FIFO_SIZE 536 bytes or bigger and 
   correspondingly shrinking MAX_TCP_SOCKETS will correct this problem.



********
v4.11       27 August 2007
********
IMPORTANT NOTE: You must use MPLAB 7.62 or higher to successfully open the 
                MPLAB projects.

Changes:
1. Added a Microchip TCP/IP Stack Users' Guide to document the stack 
   features/modules/and APIs and address the stale AN833 documentation.  Note that this 
   is a work in progress.  Many modules have yet to be documented in the Users' Guide.
2. Added HTTP2 module.  This HTTP module includes a whole new API and supreme new 
   features, such as POST support, cookies support, browser authentication support, and 
   more.
3. Added MPFS2 module.  This module is required for the new HTTP2 module and performs 
   better while having fewer limitations.  Long filenames and folders are now 
   supported.
4. Added a new GUI based MPFS2.exe PC utility.  The older MPFSv2.exe GUI application 
   and MPFS.exe command line tool has been retired.  The new utility has advanced 
   features, such as MPFS2 file format support, GZIP compress, etc.
5. Added a TFTP bootloader.  This is a stand alone project and currently only supports 
   the PIC18F97J60 family of PIC processors with internal Ethernet.
6. Added UART2TCPBridge.c file and STACK_USE_UART2TCP_BRIDGE option to TCPIPConfig.h.  
   This new module acts as a TCP and UART bridge, with a high priority UART interrupt 
   and dedicated UART TX and RX FIFOs for minimum UART latency and maximum performance.  
   By default, the bridge acts as a TCP server and listens on port 9761.  The UART baud 
   rate defaults to 19200.  The bridge can be reconfigured to act as a TCP client.
7. Added Simple Network Time Protocol (SNTP) client.  This module automatically 
   obtains the current time (date) from the Internet.  Enable this module by defining 
   STACK_USE_SNTP_CLIENT in TCPIPConfig.h.  Obtain the current time (in seconds since 
   00:00:00 1970) by calling the SNTPGetUTCSeconds() API.
8. Added support functions Base64Encode() and Base64Decode() in Helpers.c.  Base 64 is 
   required for the new HTTP2 module, but of general use to many applications. 
9. Added SMTP Authentication support to the SMTP Client.  To use this, set the 
   SMTPClient.Username and SMTPClient.Password string pointers to a non-NULL value 
   before calling SMTPSendMail().  Applications implementing email transmission 
   capabilities should expose these options to the end-user for configuration.  To use 
   SMTP servers that do not support the AUTH LOGIN authentication command, simply 
   leave the SMTPClient.Username and SMTPClient.Password pointers as their default 
   NULL value.
10.Converted DHCPDisable() from a macro to a real function and added the complementary 
   DHCPEnable() function.  These two functions can be used at run time to dynamically 
   switch between using a static IP address and configuration and DHCP assigned IP 
   address and configuration.
11.Updated StringToIPAddress() to work more robustly, including the ability to decode 
   host name strings and determine if they contain a valid IP address or not.  Also, 
   the complementary ROMStringToIPAddress() function was added.
12.Updated the DNS module.  Now, if you give it an IP address string to resolve, it 
   will convert the string to an IP address and immediately return without querying 
   the DNS.
13.Shrunk the advertised TCP Maximum Segment Size from 576 bytes to 528 bytes.  This 
   might improve compatibility if your TCP data has to propagate over nodes with small 
   MTUs and you have a correspondingly large TCP RX FIFO defined.
14.Performed some maintenance on the FTP.c file.  No significant functionality has 
   been changed, but some potential problems were corrected.
15.Altered Tick.c file and API.  Now, the Tick module can operate maximum precision, 
   returning the value of the actual Timer as it is counting, without disturbing the 
   timer count by writing to it or disabling it.  Three new APIs were added, 
   TickGetDiv256(), TickGetDiv64K(), and TickConvertToMilliseconds().  Internally the 
   tick counter is now 48-bits wide and as accurate as your Timer clock source, 
   allowing you to use it as a Real Time Clock.
16.Added PIC24FJ64GA004_PIM hardware profile.  This hardware profile is intended for 
   use with the PIC24FJ64GA004 PIM on the Explorer 16 development board.  In this mode, 
   BUTTON2 and BUTTON3 and several of the LEDs do not work correctly due to lack of 
   I/O pins on this device.  Also, you cannot have the POT and TEMP jumpers on the PIM 
   bridged because these signals are multiplexed with the SDO1/SDI1 pins needed for 
   the Ethernet PICtail Plus.
17.Removed most ROM APIs when using a 16-bit compiler (C30).  PIC24s and dsPICs usually 
   don't need separate ROM functions since the Program Space Visibility feature maps 
   ROM into RAM space.  All ROM APIs are still supported, but they are now macros to 
   base RAM APIs.  This change saves a couple of kilobytes of code space on PIC24 and 
   dsPICs.
18.Improved MyTCB structure caching.  This should reduce TCP packet processing 
   overhead with the ENC28J60 where TCBs are stored in the Ethernet RAM.
19.MAX_RETRY_COUNTS TCP configuration option has been renamed to TCP_MAX_RETRIES.
20.FTP server is no longer enabled by default.  HTTP2 now supports POST, so you can 
   upload new webpages through the /mpfsupload page now.  FTP required two precious TCP 
   sockets.
21.Began adding hooks for an SSL/TLS transport for secure HTTPS and other future stack 
   modules.  Note that these cryptographic modules are not available at this time.  
   Configuration options such as MAX_SSL_CONNECTIONS do nothing and should not be 
   modified.
22.Username has changed for all of the modules.  Now all modules have a default 
   username of "admin" and password of "microchip".  Previously, the FTP and Telnet 
   modules used "ftp" and "telnet" respectively for the usernames.

Fixes:
1. Fixed a SendFile() bug in HTTP.c where parsing dynamic cgi files could send garbage 
   back to the web browser sometimes.  Thanks go to Matt Watkins on the Microchip 
   Ethernet forum for identifying this issue.
2. Fixed an off by one error in the calculation of RESERVED_TCP_MEMORY.  Previously, 
   the last TCP socket's RX FIFO would incorrectly overlap with the Ethernet RX buffer, 
   causing incoming packets to occasionally be corrupted or the incoming data on the 
   last socket to get corrupted.
3. Fixed the QWORD_VAL's dword struct element types.  dword.LD and dword.HD were 
   incorrectly defined as WORDs instead of DWORDs.  Thanks go to Iñaki Esparza on the 
   Microchip Ethernet forum for identifying this issue.
4. Fixed the incorrect processing of received IP fragments with a non-zero offset.  
   This stack does not support IP packet reconstruction due to the limited amount of 
   available RAM.  Thanks go to Iñaki Esparza on the Microchip Ethernet forum for 
   noticing this behavior.
5. Board now only responds to ping requests to our IP address, the directed subnet 
   broadcast address, or the broadcast address of 255.255.255.255.  Previously, it 
   would respond to any ping request to any IP address, assuming the MAC address was 
   correct.
6. Fixed a memory corruption/UDP packet loss problem when handling incoming UDP 
   packets.  Previously, StackTask() would incorrectly continue processing more 
   packets if it came upon a UDP packet.  Thanks go to Iñaki Esparza on the Microchip 
   Ethernet forum for identifying this issue.
7. Fixed the SMTPClient.ROMPointers.Server flag having an inverted meaning.  
   Previously, the SMTP client module would treat the SMTPClient.Server pointer as a 
   ROM pointer if this bit was cleared.  In most cases, this would cause the SMTP 
   client to return an error code of 0x8000 when the SMTPClient.SMTPServer address 
   pointer was set.
8. Fixed the DHCP Server module from incorrectly parsing received packets which had a 
   DHCP_PARAM_REQUEST_IP_ADDRESS option followed by more options.  Previously due to 
   the length miscalculation, the parser would enter a random state, depending on the 
   packet's contents.  Thanks go to Iñaki Esparza on the Microchip Ethernet forum for 
   identifying this issue.
9. Fixed potential incorrect results when UDPIsGetReady() was called and a previous 
   application did not call UDPDiscard() on an RX packet.  Now, StackTsk() calls 
   UDPDiscard() as appropriate to let it know when it's old RX data is being thrown 
   away.  This fixes a potential bug in the DHCP Server module and makes the UDP API 
   more robust.  Thanks go to Iñaki Esparza on the Microchip Ethernet forum for 
   identifying the potential DHCP server issue.
10.Fixed a potential ARP bug where the Gateway's MAC address would be returned for an 
   IP address on the local subnet.  This unusual case would occur when two application 
   tasks were using the ARP module at the same time and the second application was 
   trying to resolve an IP address off of our subnet.  Thanks go to Iñaki Esparza on 
   the Microchip Ethernet forum for pointing this issue out.
11.Fixed an PIC18F97J60 family MAC layer bug where MACGetArray() might not correctly 
   increment the Ethernet read pointer if a NULL pointer was given for the 
   destination.  The C compiler might have optimized the function so that it would 
   increment the read pointer one less than it was supposed to.
12.The TCP module now acknowledges TCP Keep-Alive packets which will help prevent 
   connection loss if the remote node fills up our RX FIFO and then our window-update 
   packet gets lost on the network/Internet.  In stack version 4.02, a zero-window 
   probe would have been required to restore the communications.
13.Fixed a TCP RX FIFO corruption issue that would occur in (uncommon) circumstances 
   when too many out-of-order segments arrived such that a second "hole" would have 
   been required to accommodate the data.  Thanks go to Iñaki Esparza and his eagle 
   eyes on the Microchip Ethernet forum for finding this corner case bug.
14.Inline assembly in the ETH97J60.c file has been modified to accommodate the C18 
   Extended mode and C18 Auto default storage class.  Previously, the Ethernet module 
   would transmit garbage packets when using the C18 parameter stack.
15.Fixed potential buffer overflow in NBNS.c's NBNSGetName() function where an 
   unexpected string length retrieved from the packet could cause random memory 
   corruption.
16.Fixed some potential PIC18F97J60 family Ethernet module transmit lockup conditions 
   that occur on some networks.  Previously blocking while() loops would wait 
   indefinitely for the ECON1<TXRTS> bit to become clear by hardware, which the 
   hardware might never have done.
17.In MainDemo.c, a call to DelayMs() was being made using a value of 100ms.  This was 
   too long for the underlying Delay1KTCYx() C18 function and would result in a 
   shorter than expected delay when compiled with C18.  This has been fixed with a 
   loop.  Thanks go to Andy123 on the Microchip Ethernet forum for pointing this 
   problem out.
18.Fixed a potential C18 memory overlaying problem in the TickUpdate() function.  
   Previously, the local variable used in this function might have been overlayed on 
   other memory, resulting in random memory corruption as the ISR occurred.
19.The demo AJAX web pages in the TCPIP Demo App\WebPages folder now correctly display 
   and self-refresh in Firefox 2.  Previously, it would work in Firefox 1.5 and 
   Microsoft Internet Explorer, but not Firefox 2.  Thanks go to "gohsthb" on the 
   Microchip Ethernet forum for identifying this correction.
20.Rewrote the GenericTCPServer.c example to not use an application RAM FIFO for 
   buffering.  Since the TCP module implements its own FIFOing, the application has 
   limited need for its own FIFO too.  This fixes a previous bug where the 
   GenericTCPServer was not checking the number of incoming bytes with the remaining 
   size available of the App FIFO.  This would have previously resulted in a buffer 
   overflow, corrupting the RX data if too much arrived all at once.
21.Fixed a potential MPFS classic inline ASM30 assembly code problem where web pages 
   stored in internal Flash and C30 with optimizations enabled could result in data 
   corruption.
22.Fixed a UDPPut() tracking problem that would result in extra bytes being appended 
   to the end of a packet if the UDPSetTxBuffer() function was used.  This previously 
   caused the SNMP module to send some junk data at the end of its packets.
23.Fixed a potential TCP problem where transmitted FIN packets might not get 
   retransmitted properly if the remote node never acknowledged the data that was 
   transmitted just before the FIN was sent.
24.Fixed a NetBIOS Name Service bug where the response packet would sometimes get sent 
   to an incorrect address.  It now consistently responds to the unicast MAC/IP 
   address of the NBNS query packet.
25.Added padding to all transmitted DHCP messages to make the minimum UDP payload at 
   least 300 bytes.  This fixes compatibility with some older BOOTP relay devices 
   which discard smaller packets.  Thanks go to Dave Collier on the Microchip Ethernet 
   forum for pointing this problem out.
26.Substantially shrunk the number of retransmission attempts made in the 
   TCP_SYN_RECEIVED state.  This improves recovery time when attacked by a SYN flood 
   Denial of Service event.  The recovery time is now 7 seconds (3 total packets) 
   instead of 31 seconds (6 total packets)
27.Fixed the possibility of the NetBIOS Name Service module giving out the board's 
   static IP address before a DHCP lease could be obtained.  NBNS requests are now 
   only serviced when originating from nodes on the same subnet.
28.Fixed storage of MPFS classic in internal program memory when using the HI-TECH 
   PICC-18 compiler.
29.Substantially revised TCP.c, fixing many TCP bugs and possibly adding new ones.  
   Thanks go to Michael Rubinstein for finding several of these TCP problems.
30.The DNS client module will now time out and return failure if the DNS server cannot 
   be ARPed or does not respond to the DNS query.  Each timeout is set to 1 second and 
   3 total ARP and 3 total DNS query attempts are possible.  Previously, it would 
   retry indefinitely, causing the calling application to deadlock.

Known Problems:
1. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
2. TFTPc module has not been tested with this version.
3. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to reenable it's DHCP server.
4. HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.
5. HI-TECH PICC-18 projects will not correctly set the processor configuration fuses 
   through code using the __CONFIG() macro.  Ensure that the configuration fuses are 
   manually set correctly via the MPLAB IDE Configuration Bits dialog.  This problem 
   has been observed with compiler version 9.50PL3.


Testing and Performance Notes:
1. Make sure to use MPLAB IDE 7.62 or higher with this version.  Versions below 7.61 
   will not work.  Version 7.62 has cool new features like C auto-word complete and 
   function parameter tooltips that can be enabled (disabled by default).
2. Testing was done using MPLAB C18 version 3.12, MPLAB C30 version 3.01, and HI-TECH 
   PICC-18 version 9.50PL3.  Make sure to upgrade your tools to at least these 
   versions.


********
v4.02       10 April 2007
********
IMPORTANT NOTE: You must use MPLAB 7.41 or higher to successfully open the 
                MPLAB projects.
IMPORTANT NOTE2:If an external serial EEPROM memory is used to store AppConfig, 
                it's contents will be invalidated the first time you run this 
                version, restoring the AppConfig defaults.  The AppConfig 
                structure has been optimized.
IMPORTANT NOTE3:If an external serial EEPROM memory for MPFS, you will need to 
                recreate the MPFS image and program your EEPROM.  A 32 bit 
                addressing format is now used.

Changes:
1. Implemented TCP RX packet order correction logic.  The stack can now accept 
   TCP frames that arrive out-of-order without requiring the remote node to go 
   through a retransmit cycle.  This dramatically improves RX performance when 
   communicating over the Internet.
2. UDPOpen() now can handle a NULL pointer for remoteNode.  In this case, the 
   broadcast IP/MAC addresses will be used for the remoteNode (destination 
   address of outbound packets).
3. Recreated MPLAB projects for the HI-TECH PICC-18 compiler. These were 
   temporarily absent from 4.00RC.  This project works with the PIC18F97J60 
   with internal Ethernet module, assuming the correct compiler version is 
   present.
4. Moved all the headers around.  Most of them are in 
   "Microchip Solutions\Microchip\Include\TCPIP Stack" now.  This change was 
   made to again be more compatible with other (future) Microchip software 
   libraries.
5. New UDPPut() behavior.  Now, if space in the Ethernet TX buffer runs out, 
   the packet will not automatically be transmitted.  You must call UDPFlush() 
   to cause the packet to be transmitted.
6. Added UDPGetArray(), UDPPutArray(), UDPPutROMArray(), UDPPutString() and 
   UDPPutROMString() user API functions.  These functions perform substantially 
   better than calling UDPPut() successively and allow greater application 
   programming flexibility.
7. Changed TCPPutString() and TCPPutROMString() APIs to now return an updated 
   string pointer instead of a count of bytes successfully placed in the TX 
   buffer.
8. Added UDPPerformanceTest.c.  By default this module causes UDP packets 
   containing 1024 bytes of application data to be broadcasted on UDP port 
   12345.  Use a packet sniffer, such as Wireshark (http://www.wireshark.com/) 
   to capture and derive stack overhead/UDP TX performance characteristics with 
   this module.  Note that this test uses the UDPPutROMArray() function.  
   Applications which use successive calls to UDPPut() will be slower.  To 
   enable this module, #define STACK_USE_UDP_PERFORMANCE_TEST in TCPIPConfig.h.
9. Added TCPPerformanceTest.c.  By default this module listens on TCP port 
   12345.  When a remote client connects, this server module will being 
   transmitting the maximum possible amount of application data that it can, 
   given your TCP TX FIFO size.  Use a packet sniffer, such as Wireshark 
   (http://www.wireshark.com/) to capture and derive stack overhead/TCP TX 
   performance characteristics with this module.  Any TCP client can be used, 
   including readily available utilities such as the telnet.exe utility 
   available on Microsoft Windows XP.  To use it to connect to the test module, 
   run: "telnet.exe xxx.xxx.xxx.xxx 12345" where xxx.xxx.xxx.xxx is the board's 
   IP address.  Note that this test uses the TCPPutROMArray() function.  
   Applications which use successive calls to TCPPut() will be slower.  To 
   enable this module, #define STACK_USE_TCP_PERFORMANCE_TEST in TCPIPConfig.h.
10.Added Reboot.c module.  By default, this module listens on UDP port 30304.  
   If the application byte 0x00 arrives on this port, the PIC will reset.  This 
   is primarily useful for remote Bootloader entry.  
   #define STACK_USE_REBOOT_SERVER in TCPIPConfig.h to enable this module.  
   Note that since no encrypted challenge/response algorithm is currently 
   implemented, this module is a Denial of Service vulnerability, so it should 
   not be enabled unless there is a specific need for it.
11.Made the TickUpdate() ISR routine execute in the low priority ISR instead of 
   the default high priority ISR.  The Microchip TCP/IP stack does not need any 
   interrupts except this low priority timer.
12.Renamed STACK_USE_DHCP macro to STACK_USE_DHCP_CLIENT
13.Added STACK_USE_MPFS macro.  
14.Changed UDPIsPutReady() to return a WORD instead of a BOOL.  The WORD is the 
   number of bytes that can be put into the buffer.
15.Changed MACGetArray() to accept a NULL pointer.  If NULL, the retrieved data 
   will simply be discarded.  This also changes the behavior of UDPGetArray() 
   and TCPGetArray() to match, throwing bytes away if a NULL pointer is given.
16.Added a very simple DHCP Server module.  This module has limitations and is 
   useful for a single client only.  Its purpose is to allow you to directly 
   connect the board to a standard PC through a crossover cable (no other 
   network nodes attached).  The server is coded to automatically disable 
   itself if the DHCP client is also enabled and another DHCP server is 
   detected on the network.  This allows both the DHCP server and DHCP client 
   to coexist without any manual reconfiguration.
17.Added DNSResolveROM() function for resolving host names that are stored in 
   program memory, ex: literal strings.
18.Added a TCP automatic transmit/window update timer.  It defaults to 
   TCP_AUTO_TRANSMIT_TIMEOUT_VAL (40ms) after the first get or put operation 
   following the last automatic transmit/window update.  This timer enhances 
   performance, especially when streaming data over the Internet where round 
   trip times can be several tens to low hundreds of milliseconds.  This also 
   improves application coding flexibility as TCPFlush() need not be called 
   anymore.
19.Added TCP delayed ACKnowledgement timer.  This conserves bandwidth by 
   transmitting fewer ACKs and prevents inadvertently influencing remote slow 
   start/collision avoidance and fast retransmit algorithms.
20.Completely rewrote ICMP (ping) server module.  It is now much smaller (ROM 
   and RAM), faster, and can handle packets of 576 bytes or larger, if no IP 
   fragmentation occurs.
21.Rewrote StackTsk() stack manager.  It is much simpler now.
22.Added TCPFind(), TCPFindArray(), and TCPFindROMArray() user API functions.  
   These functions peek inside a given TCP socket's RX FIFO (without removing 
   anything) and looks for a particular byte or array of bytes.  This should 
   greatly simplify the creation of application code whenever variable length 
   fields are used (ex: text strings terminated by \r\n).  It supports case 
   insensitive text searching or binary searching, as well as an offset to 
   start searching at.
23.Added TCPGetRxFIFOFree() user API.  It returns the number of bytes of free 
   space in the TCP's RX FIFO.
24.Changed default TICK resolution to 1ms (from 10ms) and improved accuracy.
25.Added outbound ping capabilities (i.e. board can now ping another board or a 
   PC).  To enable these features, define STACK_USE_ICMP_CLIENT.  This will 
   enable several new APIs, including ICMPBeginUsage(), ICMPSendPing(), 
   ICMPGetReply(), and ICMPEndUsage().  The functions should be called in this 
   order.  See the PingDemo() function in MainDemo.c for an example of how to 
   use them.  By default, pushing BUTTON3 (left-most one) will cause a ping to 
   be sent to 4.78.194.159 (ww1.microchip.com).  The response time will be 
   displayed on the LCD (assuming your development board has an LCD).
26.Cleaned up C30 3.00 signed/unsigned warnings.
27.Removed PIC18F97J60_TEST_BOARD hardware profile support.  This stack no 
   longer supports it due to the old beta silicon (with errata) mounted on 
   these boards.
28.Added support for ROM pointers for all of the SMTP strings (To, From, CC, 
   Subject, etc.).  If you use a ROM string, you must also set the 
   corresponding SMTPClient.ROMPointers.xxx bit to let the SMTP module know 
   which type of pointer was provided.  See the SMTPDemo() code in MainDemo.c 
   for and example calling sequence using both ROM and RAM strings for the 
   various fields.

Fixes:
1. Fixed a critical TCP buffer corruption issue where the start of a TCB header 
   overlapped with the last byte of the RX FIFO from the previous socket.  This 
   bug affected version 4.00RC only.
2. ETH97J60.c, TCPIP.h, and TCPIP Stack Version.txt were correctly readded to 
   the TCPIP Demo App-C18 project using relative paths instead of absolute 
   paths.
3. UDPOpen() now dynamically assigns a local port number if you call it and 
   give it a 0x0000 port number.  This should fix some UDP applications from 
   not working (ex: DNS Client module) with some computers/routers/networks 
   which throw away traffic originating from the invalid port 0x0000 value.
4. Fixed a ENC28J60 bank selection error that would occur if an application 
   called GetCLKOUT() in ENC28J60.  By default, this function is not called.
5. UnencodeURL() function in Helpers.c is now tested and working.
6. Fixed a TCP Window Update problem when TCPGetArray() was used.  Before the 
   problem was fixed, performance could have been terrible on reception.
7. Fixed a unintended TCP connection close if the socket was idle for about a 
   minute.  Now, TCP sockets will remain open indefinitely if there is no 
   traffic going on.
8. Serial numbers >32K are now displayed correctly on the serial port as a 
   positive value when C18 is used and the board is placed in configuration 
   mode (BUTTON0 is depressed on power up).
9. HI-TECH PICC-18 compiler would previously incorrectly initialize the 
   AppConfig structure.
10.Previously a processor reset was possible when accessing items in the 
   AppConfig strucutre on 16 bit MCUs (PIC24, dsPIC) due to unaligned word 
   accesses.  This was fixed by reordering the Flags byte in the APP_CONFIG 
   structure.  
11.Rewrote DHCP client state machine, fixing the previously known problem 
   where it would not perform a new discovery if it was trying to renew a lease 
   with an offline DHCP server.
12.Fixed a critical deadlock problem in the ETH97J60.c MAC layer driver for 
   the PIC18F97J60 family Ethernet controller.  Previously, it was possible 
   (although rare) that the DMAST or TXRTS bits would get stuck set if too 
   much Ethernet traffic was received within a short interval.  Previously, the 
   MACFlush() function was unnecessarily setting TXRST, which it should not do 
   while the Ethernet interface or DMA is being used.
13.Fixed an HTTP server state machine problem where a new connection occurring 
   too soon on a previously used socket could cause the HTTP server to no 
   longer respond.
14.Fixed a potential memory corruption error in the HTTPGetVar() callback 
   which would exceed the bounds of the VarString array when returning the 
   VAR_STACK_DATE variable.
15.Fixed a TCP transmission sequence tracking problem whenever data is 
   retransmitted and new unflushed data is also in the TX FIFO.  Thanks go to 
   Matt Watkins on the Microchip Ethernet forum for identifying this issue.

Known Problems:
1. RTL8019AS MAC layer driver has not been updated for new TCP module.  Users 
   requiring RTL8019AS support should continue to use stack version 3.75.
2. I2CEEPROM.c has not been tested or completed.  Continue to use I2CEEPROM.c 
   from stack version 3.75 if this file is needed.
3. Telnet server module does not implement a lot of Telnet functions.  As a 
   result, it will likely not display correctly or work at all with some Telnet 
   clients.  The server was tested with the Microsoft telnet.exe utility which 
   is provided with Microsoft Windows.
4. TFTPc module has not been tested with this version.
5. The default demo web pages which use AJAX do not automatically refresh 
   themselves when viewed in Firefox 2.0.0.1.  Earlier Firefox versions 
   (1.5ish) probably work without any problem.
6. Files may be inaccessible in your MPFS if compiled with C18 for internal 
   flash program memory and your total MPFS content is large (around 64KB or 
   larger).  The code attempts to access the ROM memory using a near rom 
   pointer when a far rom pointer is needed.
7. If using MPLAB 7.52 all .s files that are compiled with C30 will not have 
   the corresponding object file get stored in the correct directory.  As a 
   result, if you are compiling with C30 and with MPFS_USE_EEPROM not defined 
   (i.e. storing web pages in internal program memory), the project won't link 
   (throws a undefined reference to `MPFS_Start').  As a workaround, remove the 
   Intermediates Directory in the MPLAB project.  Alternatively upgrade MPLAB 
   to a newer version.  MPLAB IDE 7.60+ may have this fixed.
8. If the DHCP client and DHCP server are used at the same time and you connect 
   two similar boards to each other (ex: two PICDEM.net 2 boards connected via 
   a crossover cable), a race condition can occur where both nodes will disable 
   their DHCP server and neither board will get a successful DHCP lease.  If 
   this unlikely scenario occurs, as a work around, simply reset one of the 
   boards to renable it's DHCP server.
9. HI-TECH PICC-18 projects may not compile when MPFS_USE_EEPROM is not 
   defined and you are trying to store web page data in internal 
   FLASH program memory.
10.HI-TECH PICC-18 projects may not compile when targeting the external 
   ENC28J60 chip on the PICDEM.net 2 development board (instead of the 
   internal Ethernet controller).  This problem only applies when a 
   PIC18F97J60 family part is the target.  I.e. it compiles correctly for the 
   HPC_EXPLORER + Ethernet PICtail.

Testing and Performance Notes:
1. This stack version was compiled and tested with the following tool versions:
   -MPLAB IDE 7.52
   -Microchip C30 version 3.00
   -Microchip C18 version 3.10
   -HI-TECH PICC-18 version 9.50PL3
2. Using the UDPPerformanceTest.c module, the stack can transmit around 
   220KBytes/second (1.75Mbits/second) of UDP application data on the 
   PIC18F97J60 with internal Ethernet @ 41.66667MHz core clock, compiled using 
   C18 3.10 with debug optimization settings.
3. Using the UDPPerformanceTest.c module, the stack can transmit around 
   392KBytes/second (3.14Mbits/second) of UDP application data on the 
   PIC24HJ256GP610 with external ENC28J60 @ 40 MIPS, compiled using 
   C30 3.00 with debug optimization settings.
4. Using the TCPPerformanceTest.c module, the stack can transmit around 
   58KBytes/second  (464Kbits/second) of TCP application data on the 
   PIC18F97J60 with internal Ethernet @ 41.66667MHz core clock, compiled using 
   C18 3.10 with debug optimization settings, over Ethernet when using a tiny 
   200 byte TX TCP FIFO.  Note that performance can be improved significantly 
   by increasing the FIFO size and performance will drop significantly if the 
   round trip TCP acknowledgement time is increased (ex: testing over the 
   Internet instead of Ethernet).
5. Using the TCPPerformanceTest.c module, the stack can transmit around 
   69KBytes/second  (558Kbits/second) of TCP application data on the 
   PIC24HJ256GP610 with external ENC28J60 @ 40 MIPS, compiled using 
   C30 3.00 with debug optimization settings, over Ethernet when using a tiny 
   200 byte TX TCP FIFO.  Note that performance can be improved significantly 
   by increasing the FIFO size and performance will drop significantly if the 
   round trip TCP acknowledgement time is increased (ex: testing over the 
   Internet instead of Ethernet).
6. Using the TCPPerformanceTest.c module, the stack can transmit around 
   178KBytes/second  (1.42Mbits/second) of TCP application data on the 
   PIC24HJ256GP610 with external ENC28J60 @ 40 MIPS, compiled using 
   C30 3.00 with debug optimization settings, over Ethernet when using a larger
   2000 byte TX TCP FIFO.  Note that performance will drop significantly if the 
   round trip TCP acknowledgement time is increased (ex: testing over the 
   Internet instead of Ethernet).


********
v4.00RC     28 December 2006
********
IMPORTANT NOTE: If an external serial EEPROM memory is used to store AppConfig, 
                it's contents will be invalidated the first time you run this 
                version, restoring the AppConfig defaults.  The AppConfig 
                structure has been optimized.
IMPORTANT NOTE2: If an external serial EEPROM memory for MPFS, you will need to 
                 recreate the MPFS image and program your EEPROM.  A 32 bit 
                 addressing format is now used.


Changes:
1. Added Simple Mail Transfer Protocol (SMTP) client module and updated 
   MainDemo.c to exercise the Email transmission functionality when a user 
   pushes BUTTON0.
2. Added beta Telnet server module.  See Known Problems section.
3. Completely revamped the TCP module.  A real transmit FIFO and receive FIFO 
   are allocated for each TCP socket now.  This greatly enhances RFC compliance, 
   communications robustness, and makes application development easier.  New 
   APIs were added for putting and getting arrays and strings (including ROM 
   variants).  Several TCP related bugs are now fixed as a result.  Please 
   report any bugs found in the new implementation.
4. Added TCPPutArray() API.
5. Added TCPPutROMArray() API.
6. Added TCPPutString() API.
7. Added TCPPutROMString() API.
8. Added TCPGetArray() API.
9. Changed TCPIsPutReady() API.  Instead of returning a BOOL, it now returns a 
   WORD.  The WORD is a count of the number of bytes that TCPPut(), 
   TCPPutArray(), etc. can immediately place in the output buffer.  MAKE SURE 
   THAT YOUR CODE DOES NOT COMPARE THE RETURN RESULT OF TCPIsPutReady() 
   DIRECTLY TO TRUE.  For example, "if(TCPIsPutReady(MySocket) == TRUE){...}" 
   must be converted over to: "if(TCPIsPutReady(MySocket)){...}".
10.Changed TCPIsGetReady() API.  Instead of returning a BOOL, it now returns a 
   WORD.  The WORD is a count of the number of bytes that TCPGet() or 
   TCPGetArray() can immediately obtain.  MAKE SURE THAT YOUR CODE DOES NOT 
   COMPARE THE RETURN RESULT OF TCPIsGetReady() DIRECTLY TO TRUE.  For example, 
   "if(TCPIsGetReady(MySocket) == TRUE){...}" must be converted over to: 
   "if(TCPIsGetReady(MySocket)){...}".
11.Changed TCPDiscard() return type from BOOL to void.
12.Removed TCP_NO_WAIT_FOR_ACK option.  It was defaulted to disabled in the 
   last two releases of the stack and is not needed with the new TCP module.
13.Updated DNS module to include two new required APIs: DNSBeginUsage() and 
   DNSEndUsage().  These functions control a one bit ownership semaphore to 
   allow multiple applications to use the DNS module in series.  If invoked 
   correctly, this will prevent unintended bugs resulting from two applications 
   trying to use the DNS module at the same time.  Old applications, such as 
   those based around the GenericTCPClient.c example must be updated to use 
   these functions.
14.Started using a new project structure and folders.  You must use MPLAB 7.41 
   or higher (stack is tested on MPLAB 7.50) to use the default 
   workspaces/projects, which include files using relative paths.  This should 
   improve compatibility with some future code libraries released by Microchip. 
   StackTsk.h was broken into TCPIPConfig.h, HardwareProfile.h, and StackTsk.h.  
   TCPIPConfig.h now includes all stack configuration options and 
   HardwareProfile.h contains all hardware options.  No macros need be globally 
   defined in MPLAB project now.  TCPIP.h is the only header applications must 
   include now, for any/all modules used.
15.Combined ARP.c/ARP.h and ARPTsk.c/ARPTsk.h into a single file pair: 
   ARP.c/ARP.h.  Applications built using a prior stack revision must remove 
   all instances including "ARPTsk.h" and replace it with "ARP.h" instead.  The 
   ARP module is now simpler, more linear (easier to read), and being in one 
   source file, allows the C compiler to optimize better.
16.Added PIC18F67J60_TEST_BOARD hardware profile to HardwareProfiles.h.  This 
   hardware profile is designed for 05-60091 (Rev 1), a development board that 
   is not in production at this time.
17.Added DSPICDEMNET1 and DSPICDEMNET2 hardware profiles to HardwareProfiles.h 
   for eventual support of the Microchip dsPICDEM.net 1 and dsPICDEM.net 2 
   demo boards.  These two boards use the RTL8019AS Ethernet controller and a 
   24LC515 EEPROM.  These changes are currently incomplete and these profiles 
   cannot be used.
18.Began rewriting I2CEEPROM.c to support 16 bit CPUs, including the 
   dsPIC30F6014 used on the dsPICDEM.net 1 and 2 demo boards.  Note that work 
   here is incomplete and cannot be used as a result -- see Known Problems 
   section.
19.Partially updated RTL8019AS.c to support 16 bit CPUs, including the 
   dsPIC30F6014 used on the dsPICDEM.net 1 and 2 demo board.  Note that work 
   here is incomplete and cannot be used as a result -- see Known Problems 
   section.
20.Updated SNMP.c to use new typedefs in GenericTypedefs.h.  Also SNMP was 
   tested in this version.  SNMP.mib was updated some to better reflect current 
   hardware.
21.Added AN870 SNMP callbacks to MainDemo.c (a feature that was missing in 
   3.xx releases).  This code will get compiled when STACK_USE_SNMP_SERVER is 
   defined in TCPIPConfig.h.
22.Removed all instances of MPFS_USE_PGRM for storing in internal FLASH program 
   memory.  Storage in internal program memory is now the default. Define 
   MPFS_USE_EEPROM to override the default and store MPFS in an external EEPROM 
   memory.
23.Decreased program memory needed for Announce.c module by about 180 bytes.  
   Multiple inline calls to UDPPut() were removed.
24.UDP checksum checking logic has been improved.  The UDP layer now avoids 
   writing the pseudo header checksum in the RX buffer.
25.Swapped endianess of the returned checksum from CalcIPBufferChecksum().  
   Rewrote CalcIPBufferChecksum() in Helpers.c.  This improves consistency.
26.Improved swapl() in Helpers.c.
27.Improved USART baud rate (SPBRG) calculation for PIC18s.  Rounding is now 
   done to chose the most optimal value and the code will automatically select 
   high baud rate mode (BRGH=1) if possible.  Additional improvements can be 
   made if using a newer PIC18 with the 16 bit baud rate generator.
28.Added GenericTCPServer.c example file to complement GenericTCPClient.c.  The 
   server is enabled by defining STACK_USE_GENERIC_TCP_SERVER_EXAMPLE in 
   TCPIPConfig.h.
29.Renamed STACK_USE_GENERIC_TCP_EXAMPLE definition to 
   STACK_USE_GENERIC_TCP_CLIENT_EXAMPLE for consistency with new server 
   example.
30.Defaulted MPFS.exe to generate binary MPFS images using 32 bit addressing.  
   MPFS.h has been modified to also default to use 32 bit addressing of 
   external EEPROM images.  You must rebuild any old MPFS images and reprogram 
   them if upgrading from a previous TCP/IP stack revision, which defaulted to 
   use 16 bit addressing.
31.Updated MPFS.exe to #include "TCPIP.h" instead of "..\Headers\Compiler.h" in 
   C files generated by the utility.
32.Added MPFSv2.exe PC utility for generating large MPFS images in program 
   memory (ASM30 code) for C30 users.  Previously, the C30 compiler placed a 
   limit of less than 32KB of total MPFS size due to the PSV window size 
   limitation on PIC24/dsPIC devices.  To get around the limitation, use the 
   new MPFSv2.exe utility to generate an .s file which can be included in your 
   project instead of the .c file generated by the traditional MPFS.exe utility.

Fixes:
1. Fixed a bug in ARPProcess() which would incorrectly send an ARP response to 
   an incorrect MAC & IP address if a TX buffer wasn't immediately available.
2. Fixed a TCP bug where TCPIsGetReady() would return TRUE even if no data was 
   left in the recieved packet.  Previously you had to call TCPGet() one last 
   time and have it fail before TCPIsGetReady() would return FALSE.
3. Modified TCP state machine.  Established connections will no longer 
   automatically close if left idle for approximately 45 seconds.  Note that 
   your application needs to ensure that no sockets unintentionally get lost 
   (For example: a server socket that received data only is established and the 
   cable breaks while connected.  In this case, the socket would never be 
   detected as being disconnected since the server never attempts to transmit 
   anything).
4. Stopped overclocking dsPIC33 and PIC24H devices.  Previously PLLFBD was 
   incorrectly set to 39 instead of 38 to yield a resulting Fosc of 84MHz 
   (42MIPS) instead of 80MHz (40MIPS) with the default Explorer 16 development 
   board.  Thanks go to Matt Watkins on the Microchip Ethernet Forum for 
   pointing this error out.
5. Corrected a bug in IP.c where IPHeaderLen would not be properly initialized 
   if a NON_MCHP_MAC was used (ex: RTL8019AS) and IPSetRxBuffer() was called.  
   This bug did not affect ENC28J60 or PIC18F97J60 family support.  Thanks go 
   to Darren Rook for identifying this issue.
6. Updated checksum checking code in ENC28J60.c for latest silicon DMA checksum 
   errata.
7. Declared TickCount in Tick.c/Tick.h as volatile and implemented an interrupt 
   safe reading procedure in TickGet().  Since this multibyte variable is 
   modified in the ISR and read in the mainline code, these changes are needed 
   to prevent rare inconsistency bugs.
8. Fixed Announce.c so the unicast remoteNode of the requesting packet would be 
   used rather than the remoteNode of the last received packet, which may not 
   be correct when transmitting.  Thanks go to Brett Caulton for identifying 
   this issue.
9. Fixed a DHCP bug which would cause DHCP renewals to continually occur after 
   only 60 seconds once the original lease expired.  Thanks go to Brett Caulton 
   for identifying this issue and fix.
10.Fixed a potential TCP socket leak in the FTP module.  Previously 
   FTPDataSocket would not be reliably initialized nor closed if the connection 
   was killed forcefully (user killed application, cable disconnected while 
   transferring, etc.).

Known Problems:
1. RTL8019AS MAC layer driver has not been updated for new TCP module.  Users 
   requiring RTL8019AS support should continue to use stack version 3.75.
2. I2CEEPROM.c has not been tested or completed.  Continue to use I2CEEPROM.c 
   from stack version 3.75 if this file is needed.
3. Telnet server module is still in development.  No user authentication 
   features are currently implemented.  Some telnet clients may render the 
   telnet server output incorrectly (in the wrong locations or wrong colors).  
   Testing has only been done with the Microsoft Windows telnet.exe utility 
   that comes Windows XP.
4. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease is offline.  The board will continue to 
   use the expired IP address until the DHCP server comes back online, at which point 
   the lease will be renewed or a new discovery will occur.  A new discovery should
   occur after timing out, instead.  It is believed that this problem has always 
   existed in previous stack revisions.
5. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease does not include Option 54, the Server 
   Identifier.  A new discovery should occur after timing out.  It is believed that 
   this problem has always existed in previous stack revisions.
6. TFTPc module has not been tested with this version.
7. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).



********
v3.75       14 August 2006
********
Changes:
1. Added beta DNS client module (DNS.c).  DHCP was also updated to obtain a DNS 
   server address.  Added AppConfig.PrimaryDNSServer IP address.  Added STACK_USE_DNS 
   configuration macro.  To use the DNS client, call DNSResolve() with the server name, 
   ex: DNSResolve("www.microchip.com"), and then periodically call DNSIsResolved() 
   until it returns TRUE, ex: DNSIsResolved(&IPAddressDestination).  Only one DNS 
   resolution can be in progress at a time.  Because the DNS client is a beta module, 
   the API or code may change before being finalized.  No formal DNS API documentation 
   is available yet.
2. Added beta NetBIOS Name Service responder module (NBNS.c).  Added 
   AppConfig.NetBIOSName string.  Added STACK_USE_NBNS configuration macro.  Added 
   MY_DEFAULT_HOST_NAME macro in StackTsk.h.  Now, whenever a NetBIOS broadcast 
   attempting to resolve AppConfig.NetBIOSName arrives, a response will be made.  
   This form of name resolution only works on a single subnet.  Off the subnet, 
   manual registration in a DNS server or other means will be needed to allow the 
   local Host Name to be recognized and translated to an IP address.  The default 
   NetBIOS name for the board is "MCHPBOARD".  To test the NetBIOS Name Service 
   module, try entering http://MCHPBOARD/ into your web browser instead of the board's
   IP address.
3. Added beta HTTP client module (GenericTCPClient.c).  This module demonstrates how 
   to make a TCP client application.  To test this module, uncomment the 
   STACK_USE_GENERIC_TCP_EXAMPLE macro in StackTsk.h, recompile, and then press the 
   BUTTON1 button while the stack is running.  RemoteURL[] should be downloaded from 
   ServerName[] and written to the UART.  For the default values of ServerName[] and 
   RemoteURL[], the HTML search page for "Microchip" will be fetched from 
   "www.google.com" and written to the serial port.  No formal documentation is 
   available for this example yet.
4. Added Embedded Ethernet Device Discoverer PC project to aid in embedded product 
   discovery when connected to a network and demonstrate how to write PC applications 
   which can communicate with embedded devices.  The source code for this device is 
   included.  It can be built using the Microsoft Visual C# 2005 Express Edition 
   compiler.  At the time of stack release, this 3rd party PC development tool can be 
   downloaded at no cost from http://msdn.microsoft.com/vstudio/express/.  If using 
   only the Microchip Device Discoverer executable file without the Visual C# compiler, 
   the .NET Framework 2.0 must be installed on the local PC.  The application setup 
   utility should allow dynamic downloading of this component if the target machine 
   does not already have it installed.
5. Updated Announce.c to listen and respond to discovery requests sent to UDP port 
   30303 starting with the character 'D'.  To test this functionality, use the 
   Embedded Ethernet Device Discoverer on a PC connected to the same subnet.
6. Updated UART configuration menu to accommodate the new beta module configuration 
   options (DNS server address, device host name).
7. Increased MPFS reserve block to 64 bytes from 32.  Also, because the APP_CONFIG 
   structure was updated, all current MPFS images and data stored in deployed EEPROMs 
   needs to be updated.
8. Added a means to erase (invalidate) the onboard EEPROM using the BUTTON0 momentary 
   switch (right-most switch on demo boards with multiple switches).  To erase the 
   EEPROM, hold down BUTTON0, RESET the board (press and release MCLR switch), and 
   then continue to hold down BUTTON0 for an additional 4 seconds.  If you press MCLR 
   again, the EEPROM contents will now be invalid.  If you press '0' on the UART, the 
   same configuration that was read prior to invalidating the contents will be 
   written back into the EEPROM.  Invalidating the EEPROM allows the MY_DEFAULT_* 
   constants to get loaded into a previously programmed EEPROM chip.  Because of 
   change #7, this procedure should be done for all currently programmed EEPROMs to 
   prevent anomalous values from being read.
9. remoteNode in StackTsk.c was changed from private to global scope.  Now external 
   modules can reference the address of the last received packet.  Announce.c uses 
   this to send a unicast response to a broadcast discovery request.
10.All stack modules that can be disabled (DHCP.c, FTP.c, etc) now will no longer 
   emit a compiler error if you have it in the project without defining the 
   appropriate macro (STACK_USE_DHCP, STACK_USE_FTP, etc).  It will simply generate 
   no machine code when compiled and the stack will not use that module.  Make sure 
   the proper macro is defined for each module that you wish to use.
11.Added SetRXHashTableEntry() to ENC28J60.c.  This function can be used to set the 
   appropriate bit in the Hash Table registers to join a particular multicast group.
12.Added Realtek RTL8019AS Ethernet controller support to the stack.  MAC.c was 
   renamed to RTL8019AS.c.  This Ethernet controller is not recommended for new 
   designs.  RTL8019AS support was reintroduced to provide ongoing assistance to 
   former Application designs implementing this chip.  For new applications, use the 
   Microchip ENC28J60 or PIC18F97J60 family of microcontrollers.
13.Added I2C EEPROM support for MPFS storage.  In older 2.xx stack revisions, I2C 
   EEPROM was supported by the XEEPROM.c file.  This file has been renamed to 
   I2CEEPROM.c.  It is mutually exclusive with SPIEEPROM.c, and only one may be 
   included in the project at a time.
14.Added new hardware definitions to Compiler.h.  Pin mappings for the PICDEMNET and 
   PIC18F97J60_TEST_BOARD boards have been added.  FS_USB was also defined; however, 
   it is untested and not recommended.  See Compiler.h.  The PIC18F97J60_TEST_BOARD is 
   a non-production board that some Early Adopters of the PIC18F97J60 family parts 
   have.
15.Changed type definitions for BYTE_VAL, WORD_VAL, DWORD_VAL, and moved the generic 
   typedefs to GenericTypeDefs.h from StackTsk.h.  This should improve compatibility 
   with some future code libraries released by Microchip.
16.LCDBlocking.c module was modified to support 4-bit interfaces to LCD modules.  The 
   PICDEM.net board has the module wired using a 4-bit bus.


Fixes:
1. Fixed a serious MAC TXBuffer leak in TCP.c.  Previously TCP.c would allocate a 
   buffer for each socket in use, but under heavy traffic conditions (ex: user holds 
   down F5 on web browser), the buffer handle might have been discarded before 
   releasing the buffer.  As a result all TCP connections would have lost the ability 
   to send any application data after the TXBuffer pool ran out.
2. In the TCP_SYN_SENT TCP state, ACKs may only be received (as opposed to SYN+ACK 
   packets) if the remote node thinks the connection is already open.  A RST is now 
   sent in response to an unexpected ACK, which may improve reconnection time when 
   this (rare) condition occurs.
3. A bug was present in the UDP module where remote MAC addresses would be cached for 
   each socket, even when UDPInit() or UDPClose() was called, or the microcontroller 
   was reset.  As a result, responses to incoming packets could have been sent to the 
   wrong MAC address.  UDP Sockets are now properly initialized/closed.
4. Fixed a potential timing bug in LCDBlocking.c.  For lower values of CLOCK_FREQ, 
   insufficient delay time was given to the LCD module, potentially causing improper 
   operation.
5. Changed PIC24F to default to the XT oscillator fuse rather than HS.  The 
   PIC24FJ128GA010 data sheet, rev. C reports that 8MHz should be used with XT mode, 
   not HS mode like prior data sheets.
6. Added a couple of wait states to the Realtek RTL8019AS MAC layer module for 
   NICPut() and NICGet().  Previously, the PICmicro could not operate above 
   approximately 25MHz without losing communication with the RTL8019AS chip.
7. Updated PC based MPFS utility.  When generating C files to be added to your MPLAB 
   project, the include path to "Compiler.h" is now "..\Include\Compiler.h".  The 
   output file, ex: "MPFSImg.c" should be placed in the "Source" subfolder before 
   compiling.  For example, if you are in the main stack folder with the MPLAB 
   projects, type: "mpfs /c WebPages Source\MPFSImg.c"
8. IP Gleaning will now get properly disabled when, through the RS232 configuration 
   application, DHCP and IP Gleaning are disabled.  The stack will still respond to 
   ping requests which have the wrong destination IP address, but a correct MAC 
   address.  However, the stack will continue to keep its statically defined IP 
   address when DHCP/IP Gleaning are disabled and the ping arrives.
9. SPIEEPROM.c now saves and reconfigures the EEPROM_SPICON1 register (SSPCON1) before 
   reading or writing to the SPI.  After the read/write, it restores the saved state.  
   This allows the SPI bus to operate at different speeds, depending on what 
   peripheral is being accessed if other devices share the bus and can support 
   different speeds.  In particular, this fixes the SPI @ 10.4MHz problem on the 
   PICDEM.net 2 board when using the ENC28J60.


Known Problems:
1. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease is offline.  The board will continue to 
   use the expired IP address until the DHCP server comes back online, at which point 
   the lease will be renewed or a new discovery will occur.  A new discovery should
   occur after timing out, instead.  It is believed that this problem has always 
   existed in previous stack revisions.
2. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease does not include Option 54, the Server 
   Identifier.  A new discovery should occur after timing out.  It is believed that 
   this problem has always existed in previous stack revisions.
3. When an MPFS .c image file is added to a C30 project, a linking error reporting 
   insufficient contiguous .const memory may occur when too much data is in the MPFS 
   image (PSV window size limitation).  Using the PSV window, 1 out of every 3 program 
   memory bytes is wasted.
4. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested 
   and possibly do not work.
5. SNMP, TFTPc modules have not been tested with this version.
6. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
7. The C30 linker may misplace the __CONFIG2 section or disallow usage of MPFS images 
   that are too big (add too much to the .const code section).  The consequences of 
   this are that the first configuration word at 0x157FC may not get set through code 
   (must use the Configuration Bits dialog instead), and/or the project will not 
   compile.  This problem has been observed with C30 ver. 2.02 on the PIC24FJ128GA010 
   product.  To work around this problem, the p24FJ128GA010.gld linker script has 
   been modified.  Specifically, line 68 has been commented out, which causes the 
   linker to place all .text sections after placing all absolute sections.  SSR 25966 
   in the C30 2.02 release notes may be related.
8. It is observed with the Realtek RTL8019AS Ethernet controller and the demo AJAX 
   web page which self refreshes rapidly, that occasional HTTP GET requests sent by 
   the computer do not get received by the HTTP server.  This is believed to be a 
   RTL8019AS MAC layer bug.  The TCP protocol handles the packet loss, but 
   application performance suffers while waiting for the TCP retransmission.  This 
   problem is not observed with ENC28J60.c or ETH97J60.c MAC layers.
9. The HI-TECH compiler version 9.50PL1 crashes when compiling LCDBlocking.c with 4 
   bit mode (PICDEMNET) and using a warning level of -3 or higher.  To work around 
   the problem, the HI TECH projects were set to use warning level -4.


Guiding Notes:
1. To use the stack on a classic PICDEM.net demo board with the Realtek Ethernet 
   controller, a PIC18F452 processor, and Microchip C18:
   -Use the C18EEPROM MPLAB project
   -Change the processor in the MPLAB IDE
   -Change linker script to "18f452i.lkr" in the MPLAB project.  Use the one provided 
    in the Linker subfolder, it has been modified to make more RAM available.
   -Update the hardware definitions macro.  Click on Project -> Build Options... -> 
    Project -> MPLAB C18 -> Add PICDEMNET, remove HPC_EXPLORER)
   -Remove ENC28J60.c from the project
   -Remove SPIEEPROM.c from the project
   -Add RTL8019AS.c to the project
   -Add I2CEEPROM.c to the project
   -Enable all compiler optimizations (Project -> Build Options... -> Project -> MPLAB 
    C18 -> Categories Optimization -> Enable all)



********
v3.60       12 July 2006
********
General Information:
This stack version is being publicly released, so the following changes are with 
respect to the prior public stack release (v3.02).  Interim stack changes for version
3.16 and 3.50 are documented below for those using non-public releases, but can be 
ignored by most people.


Troubleshooting notes:
1. If you have an Ethernet PICtail revision 2.1 and are having reliability issues when 
   viewing the fast-refresh demo web page, you may need to install resistors in series 
   with the ENC28J60 SI, nCS, and SCK pins.  The recommended value is 100 to 200 ohms. 
   This will reduce signal undershoot caused by long traces (parasitic inductance), 
   which can violate the absolute maximum electrical specs and cause SPI data 
   corruption.  The HPC Explorer Rev 5 has fairly long traces to the PICtail connector.
2. Enabling C30 2.02 compiler optimizations on the dsPIC33FJ256GP710, PIC24HJ256GP610 
   ES chips may produce unreliable code.
3. When changing a C30 project to a PIC24H or dsPIC33F processor on the Explorer 16 
   demo board, the JTAG configuration fuse should be disabled to free the I/O pins 
   associated with it.  JTAG is enabled by default.
4. This stack release was tested using MPLAB 7.40, C18 version 3.03, C30 version 2.02, 
   and HI TECH PICC18 version 9.50PL1.
5. When using the Ethernet PICtail board and HPC Explorer demo boards, make sure to 
   plug the power into the Ethernet PICtail and not the HPC Explorer.  The HPC 
   Explorer's power regulator cannot provide enough current.


Changes:
1. Source files have been split into separate directories.  To compile old 
   applications with this new stack, application source files may need to be updated 
   to include the proper path to the stack header files.
2. New MPLAB projects have been created:
   -C18EEPROM: Equivalent to the previously named "mpnicee" project.  Designed for 
               PIC18's using the C18 compiler.  Web page content, board's IP address, 
               MAC address, DHCP enabled state, etc. is stored in an external SPI 
               EEPROM (25LC256 on demo boards).  FTP Server demo is included.
   -C30EEPROM: New supporting PIC24 and dsPIC controllers using the C30 compiler.  
               Similar to C18EEPROM.
   -C18ProgramMem: Equivalent to the previously named "mpnicpg" project.  Web page 
                   content stored in internal FLASH program memory.  Board's IP 
                   address, MAC address, DHCP enabled state, etc. is stored only in 
                   RAM and defaults are loaded from MY_DEFAULT_* constants in 
                   StackTsk.h.  FTP Server demo is not included.  Web pages cannot be 
                   updated remotely.
   -C30ProgramMem: New supporting PIC24 and dsPIC controllers using the C30 compiler.  
                   Similar to C18ProgramMem.
   -HTC18EEPROM: Equivalent to the previously named "htnicee" project.  Designed for 
                 PIC18's using the HI TECH PICC18 compiler.  Similar to C18EEPROM.
   -HTC18ProgramMem: Equivalent to the previously named "htnicpg" project.  Designed 
                     for PIC18's using the HI TECH PICC18 compiler.  Similar to 
                     C18ProgramMem.
3. Created hardware definitions (pins, interrupt flags, special registers, etc) in 
   Compiler.h for easy changing of hardware.  Four demo board combinations are 
   supported out-of-box now:
    -EXPLORER_16: Explorer 16 motherboard + Ethernet PICtail Plus daughter card.  
                      Tested with dsPIC33FJ256GP710, PIC24HJ256GP610, and 
                      PIC24F128GA010 ES PIMs.
    -HPC_EXPLORER: PICDEM HPC Explorer motherboard + Ethernet PICtail daughter 
                       card.  Tested with PIC18F8722 onboard and PIC18F87J10 PIM.
    -DSPICDEM11: dsPICDEM 1.1 motherboard + Ethernet PICtail daughter card 
                     (manually air wired).  See Compiler.h for proper pins to air wire.  
                     Tested with dsPIC30F6014A PIM.
    -PICDEMNET2: PICDEM.net 2 motherboard (PIC18F97J60)
   Change boards by changing the defined macro (Project -> Build Options... -> 
   Project -> MPLAB Cxx -> Add macro).  When moving to custom hardware, add an  
   appropriate profile to Compiler.h.  YOUR_BOARD is present as a placeholder.
4. Added Ethernet PICtail Plus schematic (reference ENC28J60 daughter card design for
   Explorer 16 demo board).  These boards have a Microchip part number of AC164123.
5. Latest ENC28J60 rev. B5 errata workarounds added.  The code checks the EREVID 
   register and implements the appropriate workarounds as needed for the silicon 
   revision, so rev. B1, B4, and B5 are all supported in this stack release.
6. Significantly revised demonstration web page content in WebPages folder to use 
   AJAX technology.  Using asynchronous JavaScript code executing in the web browser,
   the status sections of the page are updated rapidly from the web server without 
   doing a full page refresh.  As a result, a virtually real time update of the 
   potentiometer and button values can be displayed.  Due to the constant use of new 
   TCP sockets, multiple simultaneous users are not recommended.  See the Index.cgi 
   file for a simple static method of retrieving dynamic variables from the HTTP 
   server.
7. Changed IP Gleaning procedure.  Now, if DHCP is enabled, the DHCP module will 
   continue to look for a new IP address/renew existing IP address if the IP address 
   is configured using IP Gleaning.  Previously, the DHCP module would be disabled 
   once a successful ICMP packet was received and used to configure the IP address.
8. MAX_RETRY_COUNTS is 3 (previously it was 3, but an interim release changed it to 5).
9. Updated TCP state machine.  It now includes the TCP_FIN_WAIT_2 state.  Some other 
   changes were made to handle errors more robustly.
10.AN0String and AN1String now return all characters excluding the null terminator 
   when the HTTP server calls HTTPGetVar (except when the string is 0 length).  
   Previously, the null terminator was returned as well.
11.Dynamic pages (ie: .cgi files) are now served with an expired HTTP header to 
   prevent browser caching and allow more dynamic content to be displayed.
12.Support for the HI TECH PICC18 compiler has changed.  Special Function Register 
   bits and other definitions have changed substantially from the previous HI TECH 
   PICC18 projects in TCP/IP stack version 3.02 and earlier.  The C18/C30 SFR and 
   SFRbits naming conventions are now used and special remapping macros in Compiler.h 
   are used to maintain a consistent syntax.  The HI TECH PICC18 projects were tested 
   with compiler version 9.50PL1 on the HPC Explorer board (PIC18F8722).
13.FTP client hash printing has been added to the FTP server.  Now, whenever a chunk 
   of data is successfully uploaded to the device, a '#' character will appear on the 
   FTP client screen.  The numbers of bytes each '#' represents is variable.
14.To improve maintainability, built in support for the "Compatible" A/D converter 
   present on older PIC18 parts (ex: PIC18F452) has been removed.
15.Removed old LCD code originally provided for the PICDEM.net demo board.
16.Added LCDBlocking.c and LCDBlocking.h, which implement simple routines for writing 
   to the LCD module on the Explorer 16 and PICDEM.net 2 development boards.  The LCD 
   on the dsPICDEM 1.1 board is not supported.  The stack version and IP address are 
   shown on the LCD on power up.
17.UART functions in MainDemo.c were replaced with C18 and C30 peripheral library 
   functions.  However, because the UART peripheral libraries are not being updated 
   for newer silicon devices, the code was copied into UART.c and is compiled with 
   the stack.
18.Multiple TX buffer support has been implemented.  Most stack layers have been 
   touched.  ENC28J60.c has the most extensive changes.  Each socket may use only one
   TX buffer.
19.Implemented TCP retransmission support regardless of if TCP_NO_WAIT_FOR_ACK is 
   defined or not.
20.TCP_NO_WAIT_FOR_ACK in StackTsk.h has been undefined by default.  This should 
   increase default TCP connection robustness.  Packets sent from the stack to the 
   remote node will now be detected and retransmitted if lost or corrupted.
21.All TCP packets are now retransmitted immediately after being initially transmitted 
   when TCP_NO_WAIT_FOR_ACK is undefined.  This improves throughput greatly when 
   communicating with systems which wait a long time before transmitting ACKs.  TCP/IP 
   stacks, such as that used by Microsoft Windows, implement the TCP Delayed 
   Acknowledgement algorithm, which is why this retransmission is necessary for high 
   performance.  The double transmission feature can be disabled in the Microchip 
   TCP/IP stack by defining "DEBUG" either in the TCP.c file or the project compiler 
   macros section.  Using DEBUG mode can be useful when trying to look for errors 
   using Ethreal [ http://www.ethereal/ ].
22.Lowered TCP_START_TIMEOUT_VAL from 60 seconds to 3 seconds.  60 seconds is an 
   unreasonably long timeout for modern day network speeds.
23.Native support for the SLIP module has been dropped.



Fixes:
1. A new IP address obtained via IP Gleaning will now update the LCD (if present), 
   invoke the Announce module (for MCHPDetect.exe), and output the new address out 
   the RS232 port.
2. DHCP client will now correctly use the first DHCP offer received when connected 
   to a network running multiple DHCP servers.  Previously, the board would get no
   IP address when attached to a network with multiple DHCP servers (unless the DHCP 
   request was transmitted before a second DHCP offer was received -- a relatively 
   rare event).  Additionally, DHCPLeaseTime does not get reset to 60 seconds or 
   the value stored in the last DHCP packet received prior to receiving the ACK.
3. UDPProces() will now correctly process received UDP packets that have a 0x0000 
   checksum field.  The UDP protocol specifies that 0x0000 means the checksum is 
   disabled.  Packets with a 0x0000 checksum were previously thrown away unless the 
   calculated checksum also happened to be 0x0000.
4. The TCPIsPutReady() function will now honor the remote node's TCP window size.  In 
   other words, if the remote application pauses or cannot handle the incoming data 
   rate, the TCP flow control feature will correctly function.  Previously, if the 
   remote node ran out of incoming buffer memory, the TCP layer would still allow 
   more data to be transmitted.  This would result in the loss or corruption of 
   application data, with a potentially broken connection.  The change requires 2 more
   bytes of RAM per TCP socket (TCB array).


Known Problems:
1. On PICDEM.net 2 board ENC28J60 and 25LC256 EEPROM share the same SPI1 module.  At 
   3.3V, the 25LC256 is only rated to 5MHz SPI clock, but the code is setting it to 
   10.4MHz because the MACInit() function reconfigures the same SPI1 module.
2. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease is offline.  The board will continue to 
   use the expired IP address until the DHCP server comes back online, at which point 
   the lease will be renewed or a new discovery will occur.  A new discovery should
   occur after timing out, instead.  It is believe that this problem has always 
   existed in previous stack revisions.
3. DHCP will continually send out DHCP Request packets when the lease expires and the 
   original DHCP server that gave the lease does not include Option 54, the Server 
   Identifier.  A new discovery should occur after timing out.  It is believe that 
   this problem has always existed in previous stack revisions.
4. The MPFS utility has not been updated.  When creating a .c image file, the include 
   path for the Compiler.h file will be incorrect and need to be manually updated to
   "..\Include\Compiler.h".
5. When an MPFS .c image file is added to a C30 project, a linking error reporting 
   insufficient contiguous .const memory may occur when too much data is in the MPFS 
   image (PSV window size limitation).  Using the PSV window, 1 out of every 3 program 
   memory bytes is wasted.
6. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested 
   and possibly do not work.
7. SNMP, TFTPc modules have not been tested with this version.
8. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
9. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
10.The C30 linker may misplace the __CONFIG2 section or disallow usage of MPFS images 
   that are too big (add too much to the .const code section).  The consequences of 
   this are that the first configuration word at 0x157FC may not get set through code 
   (must use the Configuration Bits dialog instead), and/or the project will not 
   compile.  This problem has been observed with C30 ver. 2.02 on the PIC24FJ128GA010 
   product.  To work around this problem, the p24FJ128GA010.gld linker script has 
   been modified.  Specifically, line 68 has been commented out, which causes the 
   linker to place all .text sections after placing all absolute sections.  SSR 25966 
   in the C30 2.02 release notes may be related.


Guiding Notes:
1. To change processors using a C18* project:
   -Change the processor in the MPLAB IDE
   -Change linker script (ex: 18f87j10i.lkr) in the MPLAB project.  Use *i.lkr 
    if the ICD2 is going to be used to debug with.
   -Update the hardware definitions in Compiler.h or change your demo board 
    selection macro.  (Project -> Build Options... -> Project -> MPLAB Cxx -> 
    PICDEMNET2, etc)
2. To change processors using a HTC18* project:
   -Change the processor in the MPLAB IDE
   -Update the hardware definitions in Compiler.h or change your demo board 
    selection macro.  (Project -> Build Options... -> Project -> MPLAB Cxx -> 
    PICDEMNET2, etc)
3. To change processors using a C30* project:
   -Change the processor in the MPLAB IDE
   -Change linker script (ex: p33FJ256GP710.gld) in the MPLAB project.  
   -Update the hardware definitions in Compiler.h or change your demo board 
    selection macro.  (Project -> Build Options... -> Project -> MPLAB Cxx -> 
    DSPICDEM11, etc)
   -Disable JTAG configuration fuse, if enabled
4. When using the PICDEM.net 2 board, to write code targeting the PIC18F97J60 family
   Ethernet module:
   -Remove ENC28J60.c from the project
   -Add ETH97J60.c to the project
   -Plug the Ethernet cable into the left-most RJ45 jack (next to LCD)
5. When using the PICDEM.net 2 board, to write code targeting the ENC28J60 Ethernet 
   device:
   -Make sure ENC28J60.c is in the project
   -Make sure that ETH97J60.c is not in the project
   -Plug the Ethernet cable into the right-most RJ45 jack (next to board edge)
6. When using the PICDEM.net 2 board, to write code targeting an Ethernet PICtail 
   module (ENC28J60):
   -Make sure ENC28J60.c is in the project
   -Make sure that ETH97J60.c is not in the project
   -Make sure that the Ethernet PICtail J9 jumper is in the 2-3 position (default).
   -Properly update the hardware profile in Compiler.h.  ENC_CS_TRIS and ENC_CS_IO 
    need to be changed from D3 to B3.
   -Plug the Ethernet cable into the PICtail
   -Plug power into the PICDEM.net 2 board
7. When using the Explorer 16 and Ethernet PICtail Plus demo boards, make sure to mate 
   the PICtail to the motherboard using the topmost socket position, leaving the cable 
   hanging over prototyping area.  If SPI2 is desired, the PICtail should have the 
   same orientation but be installed in the middle slot.  Using SPI2, the hardware 
   profile will need to be updated in Compiler.h.



********
v3.50       13 April 2006
********
Changes:
1. Improved dsPIC33F and PIC24H support.  UART functions are included now instead of 
   precompiled object files for the PIC24F.  The 12-bit A/D converter is now shown in 
   use on the demo web content.  When changing a C30 project to a PIC24H or dsPIC33F 
   processor on the Explorer 16 demo board, the JTAG configuration fuse should be 
   disabled to free the I/O pins associated with it.  JTAG is enabled by default.
2. Added LCDBlocking.c and LCDBlocking.h, which implement simple routines for writing 
   to the LCD module on the Explorer 16 development board.  The stack version and IP 
   address are shown on the LCD on power up.
3. Added "C18ProgramMem" and "C30ProgramMem" MPLAB projects for MPFS storage (web page 
   content) on on-chip program memory.  These projects are equivalent to the previously 
   named "mpnicpg" project in prior stack releases.
4. Multiple TX buffer support has been implemented.  Most stack layers have been 
   touched.  ENC28J60.c has the most extensive changes.  Each socket may use only one
   TX buffer.
5. Implemented TCP retransmission support when TCP_NO_WAIT_FOR_ACK is undefined.
6. TCP_NO_WAIT_FOR_ACK in StackTsk.h has been undefined by default.  This should 
   increase default TCP connection robustness.
7. All TCP packets are now retransmitted immediately after being initially transmitted 
   when TCP_NO_WAIT_FOR_ACK is undefined.  This improves throughput greatly when 
   communicating with systems which wait a long time before transmitting ACKs.
8. Lowered TCP_START_TIMEOUT_VAL from 60 seconds to 3 seconds.
9. Increased MAX_RETRY_COUNTS from 3 to 5 times.
10. The example HTTP server now returns a content expiration date which has already 
    past.  This prevents web browser caching and allows more dynamic content to be 
    displayed.
11. Added WebPages_JScript folder, with new web pages that support dynamic page updates 
    without a full page reload.  A tiny page of dynamic variables is returned by the 
    web server and Javascript executing on the target web browser changes DOM elements 
    as needed.  Button S5 (RA7) on the Explorer 16 demo board and S1 (RB0) on the HPC 
    Explorer demo board changes the page color scheme.  The rapid dynamic updates do 
    not work on some web browsers (Internet Explorer works, Firefox does not).


Known Problems:
1. MPFS utility has not been updated.  When creating a .c image file, the include path
   for the compiler.h file will be incorrect and need to be manually updated.
2. When an MPFS .c image file is added to a C30 project, a linking error reporting 
   insufficient contiguous .const memory may occur (PSV window size limitation).
3. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested and 
   possibly do not work.
4. SNMP, TFTPc, SLIP modules have not been tested with this version.
5. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
6. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
7. The IP address being outputted out the RS232 port and through the Announce module 
   does not happen when the IP address is configured using IP Gleaning.
8. On the PIC24F with C30 compiler optimizations enabled (such as Option 3, maximum 
   speed), the project may not work.  The PIC24F headers that come with C30 ver. 2.01 
   declare several SFRs without using the volatile keyword.
9. dsPIC30 support is incomplete.  Currently PIC18, PIC24F, PIC24H, and dsPIC33F 
   processors are supported.  



********
v3.16.00:       06 March 2006
********
Changes:
1. Added unified support for both the Microchip C18 and C30 compilers.  The intention
   is to allow one code base to be compiled for any PIC18, PIC24F/H, dsPIC30, or 
   dsPIC33 product (with adequate memory).  See the "Tested Using" section for what is
   known to work.
2. To improve maintainability, support for the HI-TECH PICC18 compiler has been 
   dropped.
3. New project workspaces have been created, "C30EEPROM.mcw" and "C18EEPROM.mcw".  
   C18EEPROM.mcw is equivalent to the previously named "mpnicee.mcw."  C30EEPROM is 
   intended to be used for PIC24 and dsPIC 16-bit controllers.
4. Source files have been split into separate directories.
5. Latest ENC28J60 rev. B5 errata workarounds added.  The code checks the EREVID 
   register and implements the appropriate workarounds as needed for the silicon 
   revision, so rev. B1, B4, and B5 are all supported in this stack release.
6. Removed old LCD code originally provided for the PICDEM.net demo board.
7. To improve maintainability, built in support for the "Compatable" A/D converter 
   present on older PIC18 parts (ex: PIC18F452) has been removed.
8. UART functions in MainDemo.c were replaced with C18 and C30 peripheral library 
   functions.

Tested Using:
1. Software:
   -MPLAB version 7.31.01
   -C18 version 3.02
   -C30 version 2.01
2. Hardware:
   -PICDEM HPC Explorer rev. 4 (PIC18F8722) + Ethernet PICtail Daughter Board (ENC28J60 
B1)
   -Explorer 16 rev. 4 (PIC24FJ128GA010 ES and dsPIC33FJ256GP710 ES) + Ethernet PICtail+ 
    Daughter card (ENC28J60 B1).
3. Notes:
   -MPLAB 7.31.01 is a development build.  The publicly available version 7.31 
    should work fine, with the exception of being unable to program dsPIC33 and PIC24H
    parts with the ICD 2.
   -No dsPIC30 or PIC24H parts have been tested yet.

Known Problems:
1. MPFS utility has not been updated.  When creating a .c image file, the include path
   for the compiler.h file will be incorrect and need to be manually updated.
2. When an MPFS .c image file is added to a C30 project, a linking error reporting 
   insufficient contiguous .const memory may occur.
3. On the PIC24FJ128GA010, it is observed that some inbound packets are lost from time 
   to time with no anticipated reason.
4. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested and 
   possibly do not work.
5. SNMP, TFTPc, SLIP modules have not been tested with this version.
6. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
7. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
8. The IP address being outputted out the RS232 port and through the Announce module 
   does not happen when the IP address is configured using IP Gleaning.
9. Multiple TX buffer support is not fully inplemented in the MAC layer, ENC28J60.c.  
   Stack behavior when TCP_NO_WAIT_FOR_ACK is undefined may be unexpected.



********
v3.02.00:       20 Feb 2006
********
Fixes:
1. Changed TXSTART in ENC28J60.c to stop wasting a byte.
2. Changed RXSTOP in ENC28J60.c to always be an odd value to properly implement an 
   ENC28J60 silicon errata workaround.
3. Changed initialization of ERXRDPT in MACInit() to agree with the current errata.

Changes:
1. Licence agreement
2. Schematics and other board files to the Ethernet PICtail Daughter Board have been 
   updated to revision 5.  Of significant note, the nRESET pin has been freed and 
   200 ohm resistors were added to the ENC28J60 SI, nCS, and SCK pins.  The added 
   resistors reduce undershoot caused by stray trace inductance and strong host output
   drivers.

Known Problems:
1. Testing on the PICDEM.net demo board with the Realtek RTL8019AS Ethernet controller 
   has not been done.  Moving to the HPC Explorer demo board has resulted in pinout 
   and other hardware changes.
2. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested and 
   possibly do not work.
3. SNMP, TFTPc, LCD, SLIP modules have not been tested with this version.
4. The stack may behave incorrectly if compiled using the Hitech compiler with a high 
   optimizations setting.
5. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
6. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
7. The IP address being outputted out the RS232 port and through the Announce module 
   does not happen when the IP address is configured using IP Gleaning.
8. Multiple TX buffer support is not fully inplemented in the MAC layer, ENC28J60.c.  
   Stack behavior when TCP_NO_WAIT_FOR_ACK is undefined may be unexpected.


********
v3.01.00:       18 Jan 2006
********
Fixes:
1. Implemented latest ENC28J60 silicon errata workarounds.
2. Fixed a bug in TCP.c and UDP.c which would incorrectly write the packet checksum 
   into the RX buffer incorrectly when the checksum field was exactly spanning the RX 
   wrapparound boundary in the ENC28J60.  This problem would have caused packets to be 
   discarded in rare circumstances


Known Problems:
1. Testing on the PICDEM.net demo board with the Realtek RTL8019AS Ethernet controller 
   has not been done.  Moving to the HPC Explorer demo board has resulted in pinout 
   and other hardware changes.
2. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested and 
   possibly do not work.
3. SNMP, TFTPc, LCD, SLIP modules have not been tested with this version.
4. The stack may behave incorrectly if compiled using the Hitech compiler with a high 
   optimizations setting.
5. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
6. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
7. The IP address being outputted out the RS232 port and through the Announce module 
   does not happen when the IP address is configured using IP Gleaning.
8. Multiple TX buffer support is not fully inplemented in the MAC layer, ENC28J60.c.  
   Stack behavior when TCP_NO_WAIT_FOR_ACK is defined may be unexpected.


********
v3.00.00:       16 Jan 2006
********
Changes:
1. The stack now targets the PICDEM HPC Explorer demo board (PIC18F8722 MCU) with an 
   attached Ethernet PICtail Daughter Board (with the Microchip ENC28J60 Ethernet 
   controller).
2. IP Gleaning is no longer enabled (STACK_USE_IP_GLEANING is not defined) by any of 
   the default project files.
3. The IP address, whenever it changes, is outputted out the RS232 serial port in 
   human readable form.  Any terminal program, such as HyperTerminal can be used to 
   read it.  This allows the IP address to be easily determined when DHCP is used.  
   The serial port defaults to 19200 baud when CLOCK_FREQ in Compiler.h is properly 
   defined.


Additions:
1. Microchip ENC28J60 Ethernet controller support.  Support is included through the 
   ENC28J60.c and ENC28J60.h files.  Various other files were modified to take 
   advantage of ENC28J60 specific features, like the hardware DMA/IP checksum engine.  
   This new MAC driver incorporates several new functions which can be called from any 
   layer above the MAC.  The functions are:
      MACSetDuplex()
      MACPowerDown()
      MACPowerUp()
      MACSetPMFilter()
      MACDisablePMFilter()
      CalcIPBufferChecksum()
      MACCalcRxChecksum()
      MACCalcTxChecksum()
      MACCopyRxToTx()
   See the ENC28J60.c file comments for function descriptions.  The ENC28J60.c file 
   also incroporates TestMemory() which can do a power on self test of various hardware 
   functions.  TestMemory() is included and used when MAC_POWER_ON_TEST is defined in 
   StackTsk.h.  It is undefined by default.  Defining it will require some program 
   memory.
2. Announce module.  Announce.c and announce.h have been added.  When included in the 
   project, STACK_USE_ANNOUNCE must be defined.  This module will broadcast a UDP 
   message to port 30303 containing the local MAC address whenever the local IP 
   address changes.  This addition is intended to facilitate device discovery on DHCP 
   enabled networks and eliminate the need for an RS232 connection if board 
   reconfiguration is not needed. To retrieve the UDP message on your computer, use 
   the new MCHPDetect.exe program included in the \MCHPDetect subfolder.
3. The spieeprom.c file was added to support SPI EEPROM chips for MPFS storage.  
   ENC28J60.c and spieeprom.c may both be included and they will share the same SPI 
   module.


Improvements:
1. Renamed files/edited files so that the HI-TECH compiler won't raise messages stating 
   that include files were spelled wrong.
2. Moved MAX_ICMP_DATA_LEN from StackTsk.c to ICMP.h file for easier maintenance.
3. Corrected STACK_USE_SIIP typo in dhcp.c file - Thanks to Gisle J.B.
4. Implemented UDP checksum logic in UDPProcess() in UDP.c file.
5. Renamed CalcTCPChecksum() in tcp.c file to CalcIPBufferChecksum().
6. Moved CalcIPBufferChecksum() to helpers.c to reuse it for UDP checksum calculation.
7. Modified UDPProcess() in UDP.c and TCPProcess() in TCP.c to include localIP as third 
   new parameter. This makes pseudo header checksum calculation correct in both 
   functions. StackTsk.h, UDP.h and TCP.h files were also modified to reflect these 
   changes.
8. Modified TCP.C file to include compile-time check of STACK_USE_TCP define.  If it is 
   not defined, an error will be displayed.
9. Removed an unnecessary call to MACDiscardRx() when an IP packet is received but 
   fails version, options length, or header checksum tests.
10. Changed LCD code to be compile time removable by undefining USE_LCD.


Fixes:
1. IPHeaderLen in IP.c is initialized properly now when IPGetHeader() is called.
2. Under some circumstances, HandleTCPSeg() would acknowlege, but throw valid received 
   TCP packets away, resulting in loss of application data.  An invalid comparison in 
   HandleTCPSeg() has been fixed to prevent this situation from occuring.
        *** Thanks go to Richard Shelquist for identifying this problem.
3. Fixed StackTsk.c file so that if a static IP address is used and the LINK is 
   removed, the node IP address is not cleared.
4. Invalid ICMP echo replies are no longer generated for echo requests with a data 
   length of 33 (one more than the configured maximum).
5. Changed MAX_OPTIONS_LEN from 20 to 40.  The maximum IP options length is now in 
   agreement with the IP RFC.
6. Changed IPSetRxBuffer() from a macro to a function.  The function takes into 
   account any options which may be present in the header of received IP packets.  
   Previously, possible options were not taken into account when calculating the 
   offset.


Known Problems:
1. Testing on the PICDEM.net demo board with the Realtek RTL8019AS Ethernet controller 
   has not been done.  Moving to the HPC Explorer demo board has resulted in pinout 
   and other hardware changes.
2. Sometimes when the FTP sever is used, an attempt to put a file is unsuccessful.  
   The problem may be caused when an HTTP request to GET a file is made at the wrong 
   time.
3. MACSetPMFilter(), MACDisablePMFilter(), and MACCopyRxToTx() have not been tested and 
   possibly do not work.
4. SNMP, TFTPc, LCD, SLIP modules have not been tested with this version.
5. The stack may behave incorrectly if compiled using the Hitech compiler with a high 
   optimizations setting.
6. Serial numbers >32K will be displayed on the serial port as a negative value when 
   C18 is used and the board is placed in configuration mode (RB0 button is depressed 
   on power up).
7. IP Gleaning may not get disabled when, through the RS232 configuration application, 
   DHCP and IP Gleaning are disabled.
8. The IP address being outputted out the RS232 port and through the Announce module 
   does not happen when the IP address is configured using IP Gleaning.
9. Multiple TX buffer support is not fully inplemented in the MAC layer, ENC28J60.c.  
   Stack behavior when TCP_NO_WAIT_FOR_ACK is defined may be unexpected.



********
v2.20.04.01:   9/24/03
********
1. Recreated MPLAB projects to avoid problems when source is not at \MCHPStack location.


********
v2.20.04:   9/5/03
********
Fixes:
1. Modified DHCPReset() in DHCP.c to not reset DHCP state machine if it was previously 
   disabled using DHCPDisable().  This would make sure that if DHCP module was enabled
   and application had run-time disabled DHCP and network cable is disconnected, 
   stack will not clear its IP address.

2. Rebuilt mib2bib.exe file with static library options.  This fixes problem where
   one tries to execute this exe, an error occurs about missing DLLs. 
   

********
v2.20.03:   
********
Improvements:
1. When DHCP is enabled, LINK is monitored and IP address is reset on disconnect.
   New IP configuration is obtained on LINK reconnect. - For RealTek only.
   Modified DHCP.c to add DHCPReset()
   Modified MAC.c to add MACIsLinked()
   Modified StackTsk.h to add BYTE_VAL def.
   
Changes:
1. Modified SMSC91c111.c to add empty MACIsLinked() - will be populated in next rev.
   
Bug Fixes:
1. Corrected DHCP logic to accept first DHCP offer instead of second response.
2. Corrected DHCP logic to check for chaddr in DHCP offer and accept one that
   matches with local MAC address.  This will fix problem where if multiple
   nodes were on bus and all requested DHCP address, all would accept response
   from one server instead of verifying who was intended node.
3. Fixed UDPClose() in UDP.c to use INVALID_UDP_PORT instead of INVALID_UDP_SOCKET
   because of which a closed socket would not be scanned correctly.
4. Modified UDP.h to use long contsant designators for INVALID_UDP_OPRT 
   to explicitly state that it is a long.   



********
v2.20.02:   
********
Beta version containing TFTP client module.

Addition:
1. TFTP Client module - See TFTPc.* and TFTPcDemo.c for more information.
   See MpTFTPcDemo and HtTFTPcDemo projects for build information.

Bug Fix:
1. UDPIsGetReady() was modified to overcome compiler rule where only 8-bit value was
   used to evaluate non-zero condition.
2. ARPResolve() in ARPTsk was fixed to clear Cache.IPAddr value.

********
v2.20.01:   
********
Bug fix:
1. Fixed SMSC91C111.c where MACInit() would hand if ethernet link is not detected.


********
v2.20:   
********
Bug Fixes:
1. General  - Removed most of harmless warnings.
2. C18Cfg.asm - Fixed "include" instead of "define".
3. DHCP.c   -   Increased DHCP_TIMEOUT_VAL to 2 seconds.
                Fixed problem where UDP active socket was not set before calling UDP 
functions
                in SM_DHCP_BROADCAST state.
4. MAC.c    -   Fixed MACIsTxReady() where under heavy traffic it would always return 
FALSE.                
                This fixes bug where all high level applications would stop 
transmitting.
5. TCP.c    -   Enabled portion of code that performs timeout logic even if 
TCP_NO_WAIT_ACK
                is defined.  This fixes bug where occasionally, tcp applications such as 
                HTTP server would stop working after few hours.
6. UDP.c    -   Fixed UDPGet() where it would return FALSE on last good byte.
                Fixed UDPProcess() where it was calculating incorrect length.
                
                Added bFirstRead flag with UDP sockets similar to TCP sockets
                so that whenever first UDP byte is read, MAC read pointer will be
                reset to begining of correct packet.
                This change fixes problem where if one transmits a packet while
                UDP packet is pending in a socket, next get to pending UDP socket would
                return wrong data. (This is apparent only when there is heavy network 
traffic)
                
Known Issues:
1. HiTech v8.20 PL4 with all optimization enabled may not work properly.
2. C18 "Static" and "Auto" mode may not be used - there are too many local variables to 
fit
    in standard stack of 256 bytes.  One may modify linker script file to avoid this 
limitation.

                

Improvements:
1. Modified TICK def. in Tick.h to unsigned long to support 32-bit wide SNMP tick.
2. Added SNMP Module (SNMP.c)
3. Added Two new demo projects - DemoSNMPApp and HtDemoSNMPApp.
4. Created MPLAB 6.X projects for different demo configurations.
5. MAC.c    -   Added MACGetTxOffset().
6. MPFS.c   -   Added MPFSSeek(), MPFSTell().
7. MPFSImg.*-   Rebuilt to reflect v2.20, footprint changes etc.
8. StackTsk.h-  Enhanced WORD_VAL, DWORD_VAL defs.
                Added STACK_USE_SNMP and related compile-time checks.
9. UDP.h    -   Added UDPSetTx and UDPSetRx macros.
                Moved UDP_SOCKET_INFO structure to header file.
10. WebSrvr.c-   Modifed MCHPStack version message and added DATE info to BoardSetup
                menu.
11. Added support for SMSC LAN91C111 10/100 Non-PCI ethernet controller 
            Use "SMSC91C111.C" instead of MAC.c.  
            "mpnicee_smsc" is a sample project that uses PIC18F8720 and SMSC NIC.
            "MasterDemo.c" is a main source file for above project that includes
            all modules - must use device with more than 32KB of memory.
            



********
v2.11:   
********
Bug Fixes:
1. Fixed dhcp.c to make it work with new C18 startup code.

Improvements:
1. Modified websrvr.c DownloadMPFS() to make use of compiler allocated XMODEM data block
   rather than use fixed address block starting at 0x400.


********
v2.10:   7/9/02
********
Bug Fixes:
1. Fixed HTTP Server bug where a form submission with empty parameter value would not 
   parse correctly.



********
v2.0:   5/22/02
********

********
New Modules:
********
1. Added UDP, DHCP, FTP and IP Gleaning
2. Added PICDEM.net LCD support
3. Added board setup through RS-232.

********
Improvements:
********
1. Optimized serial EEPROM access routines in terms of speed and size
    (Replaced ee256.* files with eeprom*.h)
2. Improved board setup through RS-232.

********
Known Issues:
********
1. LCD may not display properly on MCLR only.
   Workaround: 1. Debug XLCDInit() routine in "xlcdlh" 
               2. Always do POR reset.

2. SLIP connection is not very robust.
   Workaround: None at this time.

3. Hi-Tech Compiler: 
                1. Aggressive optimization breaks the functionality.
                   Workaround: Apply optimization listed in each source file comment 
header.
                2. In order to use V8.12, you will need to remove "FTP Server" from 
Ht*.pjt.
                   You will also need to disable all optimizations.

4. C18 Compler: 1. Static model does not compile.
                   Workaround: None at this time.
                2. Overlay model breaks the functionality.
                   Workaround: None at this time.
                3. All modules does not fit in 32KB memory.
                   Workaround: 1. None at this time.
                               2. Sample project disables some modules.


********
New Files:
********
========================================================================================
====================================
    File        Purpose
========================================================================================
====================================
1. delay.*      Provides CLOCK_FREQ depenent delay routines.
2. dhcp.*       DHCP client support
3. ftp.*        FTP server
4. udp.*        UDP socket support
5. xeeprom.*    Improved ee256.* and renamed.
6. xlcd.*       External LCD support.
7. version.log  To track changes and history.

    
********
Changes:
********
========================================================================================
====================================
    File        Change                                                                  
To-do for v1.0 stack applications
========================================================================================
====================================
1. arptsk.c     1. Fixed STACK_CLIENT_MODE compile errors.                              
None
                2. Modifed ARPIsResolved() to support IP Gleaning                       
None

2. c18cfg.asm   1. Added PIC18F452 configuration                                        
None
                2. Fixed "include" errors.                                              
None

3. compiler.h   1. Included "stdlib.h" in both C18 and Hi-Tech compilers.               
None
                2. Moved CLOCK_FREQ from "stacktsk.h" to this file.                     
None
                3. Added PORTA defs.                                                    
None

4. htnicee.pjt  1. Removed "ee256.c".                                                   
None
                2. Added "udp.c", "dhcp.c", "ftp.c", "xlcd.c", "xeeprom.c" files        
Add these files if needed.

5. htnicpg.pjt  None

6. htslee.pjt   1. Removed "ee256.c".                                                   
None
                2. Added "ftp.c", "xlcd.c", "xeeprom.c" files                           
None

7. http.c       1. Included compile-time verification that HTTP module is included.     
None
                2. Put HTTP message strings into one array "HTTPMessages".              
None
                3. Modified to return "Service Unavailable" message if MPFS is being    
None
                   remotely programmed.
                4. Modified SendFile() to make use of sequential EEPROM read.           
None

8. ip.c         1. Added one more paramter to IPGetHeader() to support IP Gleaning      
Custom apps using IP needs to be
                                                                                        
modified.

9. mac.c        1. Replaced fixed delay routines with CLOCK_FREQ dependent              
None
                   routines

10. mpfs.c      1. Replaced ee256.h with xeeprom.h.                                     
None
                2. Added MPFSFormat(), MPFSPut() etc. routines                          
None
                3. Added sequential read and page write operations                      
Custom apps using MPFS directly
                                                                                        
needs to be modified.
                4. Defined MPFS_WRITE_PAGE_SIZE for MPFSPut operations.                 
Apps using different EEPROM page size
                                                                                        
needs to be modified.
                
11. mpnicee.pjt 1. Removed "ee256.c"                                                    
None
                2. Added "xcld.c", "xeeprom.c" files                                    
None

12. stacktsk.c  1. Replaced ee256.h with xeeprom.h                                      
None
                2. Added IP Gleaning and DHCP support.                                  
None
            
13. stacktsk.h  1. Moved CLOCK_FREQ to compiler.h                                       
None
                2. Added STACK_USE_DHCP, STACK_USE_FTP_SERVER etc. options              
None
                3. Added compile-time enable/disable of modules based on selection
                   of higher level modules.                                             
None
                4. Modified MY_DEFAULT_MAC_BYTE? to use Microchip OUI id.               
None
                5. Added compiler-time check to confirm available TCP sockets           
None
                6. Added MSB and LSB macros.                                            
None
                7. Added SerialNumber etc. to AppConfig structure                       
None
                8. Commented module selection defines: They are defined by cmopiler     
None
                   command-line options.
                   Real application should define them here in this file.

14. tcp.c       1. Moved TCP_STATE and TCP_INFO to .h file.                             
None
                2. Fixed TCPIsConnected()                                               
None
                3. Fixed TCPDisconnect()                                                
None
                4. Modified TransmitTCP() to set receive window of one segment          
None
                5. Modified TransmitTCP() to use max segment size equal to
                   predefined value.                                                    
None
                6. Improved TCP State machine                                           
None

15. tick.c      1. Modified TICK type to 16-bit.                                        
None
                2. Made use of TICK_PRESCALE_VALUE                                      
None
                3. Added code to blink PICDEM.net "System LED"                          
Remove if not required.

16. websrvr.c   1. Added LCD support                                                    
N/A
                2. Made TickUpdate() on Timer0 interrupt                                
N/A
                3. Added code to save/restore board configuration                       
N/A
                4. Added board setup via RS-232.                                        
N/A
                5. Added call to FTP modules                                            
If needed, add this.
