txzm.doc

这个程序是用于通讯的

                  rate, hardware  flow control,  and have a  small internal
                  buffer.  8 works fine with USRs.

              -m  Disable modem status register interrupts.  This option is
                  another patch to accommodate Western Digital's version of
                  the  16550.  Some WDC16550s  lock up if  the modem status
                  lines (CTS,  CD, etc.)  are not  connected  to a  driving
                  signal.   This could happen  if the serial  or null modem
                  cable being used does not have all signal lines connected
                  (very possible  with  a  null  modem cable).    Using  -m
                  prevents this  problem.   It also disables  hardware flow
                  control and  carrier detect,  however, so if  you require
                  either of these and have a  WDC16550 you must use a cable
                  with all appropriate lines connected.






        Examples:

            txzm -p -s (c:\)   // send all files on drive C -- include
                               // complete path information

            txzm -p -r         // accept complete pathnames -- if path
                               // does not exist, create it

            txzm -p -r d:\temp // accept complete pathnames but put files
                               // and created directories under D:\TEMP

            txzm -r            // receive to current directory, if path
                               // information is received it is ignored

            txzm -s (\project\*.c) (\project\*.h)  // Sends all .c and .h
                               // files in the subdir PROJECT and all subs
                               // under project.  Does not send pathnames.

            txzm -u -r \dnlds  // start in mini-terminal mode, received
                               // files are placed in "\dnlds" directory

            txzm com2 -u       // mini-terminal mode, use COM2

            txzm -l38400 -b9600 -h -s file1.zip file2.zip
                               // 38400 baud locked rate, 9600 CONNECT,
                               // hardware handshake, send file list

            txzm -b2400 -u     // 2400 baud, mini-terminal mode

            txzm -c2e0,7 -r    // custom serial port at 2E0h on IRQ7,
                               // use current baud rate, receive

            txzm com2 -b115200 i u  // 115200 baud, ignore carrier detect,
                               // mini-terminal mode

            txzm -e2 -r        // COM1, current baud rate, receive, create
                               // duplicate name if file exists

            txzm -s @filelist  // send all files listed in "filelist"
                               // the name "filelist" is an example only


            Other than  the -r and -s  switches that must appear  last on the
        command  line if used, neither case nor switch order are significant.
        Also you may  use a '/' instead  of a '-' or no  switch identifier at
        all.  Ex: "txzm i E2 -u /b2400 r" is legal syntax.






                                    GENERAL NOTES

            TXZM  is faster than any other zmodem  protocol driver I am aware
        of.  It will run at 95% efficiency in both send  and receive modes at
        115200 baud on an 8 MHz 286 with a 16550 UART.  This translates to an
        effective throughput  of 110 Kbps.  In a PC Magazine (Apr 91) article
        reviewing  various communications software  packages, the BEST zmodem
        operated at less than 50 Kbps when tested at 115200 baud on the  same
        type of equipment (8 Mhz 286's with 16550 UARTs).  TXZM is over twice
        as  fast.    The review  covered  several  well  known shareware  and
        commercial packages.

            TXZM was also tested on a 4.77 MHz 8088 laptop that contained the
        functional equivalent of  a 16450 UART (no FIFOs) and  a 4.77 MHz IBM
        XT  (true blue IBM)  that had 16550  UARTs installed.   On the laptop
        system TXZM could  send most  efficiently at 23040  baud and  receive
        most  efficiently at  28800 baud.   The XT,  with 16550  UARTs, could
        receive  at a  full 38400 baud  but with  the baud rate  set to 38400
        could only achieve an effective throughput rate of around 35000 baud.
        The  tests were  performed using  the systems' hard  drives (original
        slow hard  drives), not a  RAM disk,  which also had  some impact  on
        speed.   With 16550 UART's,  TXZM could very effectively  work a high
        speed modem (HST, V.32, or V.32bis) even on a slow 4.77 MHz computer.

            If you compare the  CPS rating stated by TXZM and other programs,
        you may  find TXZM reporting slightly lower rates.   This is due to a
        difference  in the  calculation method  TXZM uses  only.   Many other
        progams  appear to fudge a little bit  on their statistics.  At lower
        speeds or  on fast CPUs all  Zmodem drivers will run  about the same.
        The speed difference shows up when the system is under a load such as
        with extremely high baud rates or  moderately high baud rates on slow
        CPUs.


                                     BBS SUPPORT

            TXZM  now recognizes  the TXZMLOG  environment variable  and will
        create a log file  with the same format as the one  created by DSZ if
        DSZLOG is set.  This was added primarily to support BBS software that
        uses DSZLOG format log files to track downloads, efficiency, etc.  If
        all you  want is a  log file you  can set TXZMLOG  only.  If  you are
        using BBS software that looks for a DSZLOG variable, you will have to
        also set DSZLOG to the same value as TXZMLOG.  Ex:

              set TXZMLOG=C:\BBS\ZMODEM.LOG
              set DSZLOG=C:\BBS\ZMODEM.LOG

            I did not use DSZLOG to avoid infringing on any non-public domain
        features of DSZ.  If you want to patch  your personal copy of TXZM to
        use DSZLOG  directly rather than TXZMLOG, you  can use a utility such
        as Norton  Utilities or  PC Tools  to  scan TXZM.EXE  for the  string
        "TXZMLOG" and  change it  to "DSZLOG".  This is  only  patch you  are
        authorized to  make. DO  NOT under  ANY circumstances  distribute ANY
        modified version.






            It is also now possible to specify a file that contains a list of
        the files to  be sent.  This is  also primarily for BBS support.   To
        use this option precede the file containing the list of files with an
        '@'  sign.   The  files  may be  separated  by  any valid  whitespace
        characters including spaces, tabs, carriage returns, line feeds, etc.

            The -q option has been added as of version 2.10 for BBS operators
        who run under DesqView.  It causes TXZM to not mess up the  video and
        also to release CPU time when it is waiting for characters or for the
        transmit buffer to empty.  

            The -0 option will disable direct screen writes if you are  using
        command line send or command line receive options.  All screen writes
        will  be done  through BIOS  calls.   Mini-terminal mode  does direct
        writes even with the -0 option specified.  -0  does not appear on the
        help screen.

            BBS sysops  may also use TXZM free (even if you charge for access
        to your system).

                                   REVISION HISTORY

          2.24  Fixed a problem with the "recurse subdirectories" option and
                also corrected a problem that caused TXZM to not work right
                when running it in a DOS box under OS/2.

          2.22  Recompiled using a different version of the MCOMM communica-
                tions driver.

          2.21  Fixed a divide by zero error that occasionally occurred on
                restarted file transfers.

          2.20  Added support for Doorway mode (ALT = toggles it on and off).
                Added support for BBSs that autodetect ANSI capable programs.
                Added -7 switch to enable stripping high bit when in terminal
                mode.

          2.14  Minor  changes so  code will  compile without  warnings using
                BC++ 3.0  and  so that  TXZM  would automatically  trigger  a
                Qmodem download  (Qmodem requires  an "rz\r"  as well as  the
                INIT  packet -- most programs trip on the INIT packet alone).
                Also modified the -n (BBS support option) so that it took the
                name of a Maximus or Opus style LASTUSER.BBS filename  rather
                than a  node number.   Modified FIFO usage  so that TXZM  set
                FIFO buffers to 1 in terminal  mode and 8 when sending  files
                (corrects jerky display at low baud rates).

          2.10  Changed  name  to TXZM  from  ZMP.    The ZMPLOG  envrionment
                variable is now  TXZMLOG. Found out somebody else already had
                a ZMP in CP/M days.  Added DesqView aware option.  Fixed Dial
                Command  so that  it  looked at  the  connect baud  rate  and
                adjusted accordingly.   Fixed Redial  Command to  continually
                dial until a  connect was made or ESC pressed.   Added F1 for
                help  key.   Added  ALT-P so  the  modem parameters  could be
                changed manually, ALT-C so  the screen could be  cleared, and
                ALT-= for Doorway mode operation.

          2.00  First non-beta version.  Added a capture file.  Fixed a minor
                problem with the -0 option.







          1.21  Added support for  specifying files  to send in  a file  that
                contains a list of  the filenames.  Added -0  option (disable
                direct screen writes in command mode).

          1.20  Fixed  bug introduced in version 1.19 that caused a divide by
                zero error  if the total bytes  to be sent was  between 1 and
                18.  Added ZMPLOG environment variable.

          1.19  Corrected bugs in the -w and -x  options.  Fixed problem with
                negative  CPS rates  showing up  when more than  11 megabytes
                were sent.  Added the -6 switch.

          1.17  Fixed double backslash in pathnames when downloading while in
                the root directory (couldn't DL to root).

          1.16  Added support for send and  receive of complete pathnames and
                creation of  subdirectories.    This  allows  duplication  of
                entire drives or subdirectories through the serial port.

          1.10  16 bit CRC mode  now really does work.  TXZM102  was supposed
                to have fixed it but didn't.

          1.02  Fixed bug  in 16 bit CRC mode (I thought).  Fixed minor error
                in ZRPOS handler. The sender now sends a ZCRCW packet when an
                error occurs  rather than a  ZCRCG. This conforms  with Chuck
                Forsberg's Zmodem specification.

          1.01  Fixed  bug in  ZRPOS handler.   This bug  occasionally caused
                TXZM  to  trash the  screen  and  lock up  when  a ZRPOS  was
                received.

                Optimized the code.  TXZM will now operate at  115200 baud at
                95% efficiency on an 8MHz 286 (approx 11100 cps -- 2 meg in 3
                mins).  A  16550  UART  is  required  to  obtain  high  speed
                operation.

                In mini-term mode, PGDN not puts TXZM in receive mode in case
                the sender's ZRQINIT was missed.  Previously it relied on the
                incoming  ZRQINIT  to trigger  receive  mode.   It  now works
                either way.

                Added a '-v'  switch.  This  switch disables overlaying  disk
                and  serial I/O.  It also  expands the receive file buffer to
                20K bytes.  The result is 20K of data is received, serial I/O
                pauses,  the 20K is written to disk,  a ZACK is sent, and the
                sender resumes sending.

          1.00  Original version.