1. usr_modem25.zip Driver
2. XMODEM.TXT File Contents

XMODEM.TXT Driver File Contents (usr_modem25.zip)

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                  Courier V.Everything Xmodem SDL Notes

          ----------------------------------------------------

In order to better support users of non-DOS systems, the Courier can
now perform flash ROM updates via the Xmodem file transfer protocol
found in most communications software.

Modems with firmware dated prior to 4/96 must first use SDL.EXE to
install the new firmware code from within DOS. The file is available
via the USR BBS at (847) 982-5092 or on the Internet at
ftp.usr.com/usr/dl05/usrsdl.exe. After installing this SDL, the AT~X!
command will be enabled.  If the flash ROM should ever get corrupted
or downgraded, the Xmodem SDL feature will be lost, and SDL.EXE will
have to be used to return the modem to normal operation.

Modems that come from the factory with firmware dated 4/96 or later
will always have Xmodem SDL available, even in the event of flash
corruption or downgrade.

SV25.XMD is the Xmodem mode flash data file.  (This is the same
firmware that is in the SDL.EXE file, but in a different format.) This
is the file that you will send to the modem in Xmodem mode. The file
supplied with this release is for US/Canada versions of Courier
internal, external, PS/2, and Comserver modems.

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          Sending New Firmware to the Courier using Xmodem SDL

          ----------------------------------------------------

1.  Start a communications software package, such as Quick Link II or
    MacComCenter.  Adjust the settings, if necessary, so that you can
    send AT to the Courier and get an OK response.  NOTE:  If you are
    sending the file from a Macintosh computer, make sure that you do
    NOT transfer the file in MacBinary format.  In MacComCenter, for
    example, select Setup -> File Transfer and under MacBinary options,
    select "Never MacBinary."

2.  Type AT~X! <Enter>.  The Courier will respond as follows:


at~x!

SDL Xmodem file transfer - (Y)es (N)o (T)est >


    Responding with 'Y' will begin the file transfer process;
    responding 'N' will abort the process and the modem will return to
    command mode.

    ***********************************************************************
    *                                                                     *
    * Responding with 'T' will begin the file transfer process in a       *
    * "safe test mode".   Test mode will verify the operation of the file *
    * transfer process and the integrity of the .XMD flash data file,     *
    * without actually erasing or re-burning the flash chip.              *
    *                                                                     *
    ***********************************************************************


3.  Respond with 't' to start an integrity test of the XMD file, or
    'y' to begin an actual update of the flash ROM.


SDL Xmodem file transfer - (Y)es (N)o (T)est >t
* Test Mode - Flash ROM will not be modified*
Begin Xmodem file transfer now.
CC


    The Courier will begin sending 'C' characters which are used as
    part of the Xmodem protocol handshaking.
    You may now begin sending the SV25.XMD file to the Courier using
    the XMODEM-CRC or XMODEM-Checksum protocol in your communications
    software.

4.  After completion of the file transfer, the modem will display a
    result message.


at~x!

SDL Xmodem file transfer - (Y)es (N)o (T)est >t
Begin Xmodem file transfer now.
CC

SDL Xmodem file transfer completed.
Calculating CRC... OK
Resetting modem...OK


    Once you see the OK response to the Calculating CRC and Resetting
    modem messages, your software upgrade is complete, and the modem
    will reset and return to command mode.

5. If the ATI7 screen now shows a supervisor date of 2/25/97 or
   greater, enter this command string in your terminal application to
   set all the correct factory-default settings:

    AT&F1S58=0S59=0S60=0S61=0S69=0S70=0#CID=0&U0&N0&W


          ----------------------------------------------------

                       The Bootstrap Downloader

          ----------------------------------------------------

    If the flash ROM should ever become corrupted, or the modem will
    not respond to Xmodem or SDL.EXE download attempts, follow this
    procedure to activate the flash ROM bootstrap downloader:

1.  Power the Courier off.

2.  Set DIP switches 1, 5, and 10 on and 8 off. (For internal modems,
    use 1, 5, and 10 on, and 7 off.) The settings of the other DIP
    switches are ignored.

3.  Power the Courier on.

4.  Start your communications software package and send the operating
    software using the XMODEM protocol, or use SDL.EXE as with previous
    versions of the Courier firmware.

5.  Power the Courier off.

6.  Reset the DIP switches to their previous settings.

7.  Power the Courier on.

_______________________________________________________________________________________________
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