MCOMM 5.57 UPDATE NOTES

         Made a change to an internal routine that initiated transmit
         interrupts.  This change fixes 2 problems--one with some new
         UARTs that recently appeared, and the other with failed or very
         slow transmits when running a program that uses MCOMM in a DOS
         box under OS/2.

         The COMM.H header file was modified to include vector numbers
         and IRQ masks for IRQs other than 3 and 4.

         Fixed a problem with the RecurseSubdirs function in TXZM.C.  It
         sometimes lost track of the current directory if the recurse
         subdirectories option was used when sending files.

         Registered users of 5.50+ may download a free upgrade to 5.57
         by logging onto N.E.T. Datalink, 903-838-6713, and leaving a
         message to the sysop that includes:

             1) Registration number from the original disk.
             2) Whether the original registration was for "Source
                and Libraries" or "Libraries Only".
             3) Your name and address.  This must match the name and
                address the software was originally registered under
                unless you have moved.

        Please allow 3 or 4 days from the time you leave the message
        requesting the update until you call back to download it.

        Mail in updates are $10.  See ORDER.DOC if you want a mail in
        update.




                           MCOMM 5.54-5.56 UPDATE NOTES

         Up to four ports may now be opened simultaneously as long as
         they do not share port addresses, IRQ lines, or vector numbers.
         Previously the limit was 2 simultaneous ports.  The AT extended
         IRQ lines (IRQs 8 thru 15) are not supported.

         A new use for 'v_scrlm' flag in the ANSI video code has been
         implemented making it easier to develop code that emulates the
         VT100.  Setting 'v_scrlm' to -1 causes the screen and cursor
         positioning to behave properly for VT100 no scroll mode.  This
         change should have no effect on existing code.

         Fixed a bug in the video code that occurred when a backspace
         character was displayed within a string with direct writes
         enabled.  (This last change is the difference between 5.55 and
         the 5.54 beta).  Version 5.56 consisted of a change to TXZM.C
         demo to account for change in COMM_S.LIB noted in following
         paragraph.


VERY IMPORTANT:

         If your code uses the option to disable or ignore the 16550
         FIFOs, or if your code disables MSR or LSR interrupts, you must
         make some changes to your source before using the new libs.  In
         order to support port addresses above 0x0FFFh, it was necessary
         to not use the high bits of the async_open ComBase parameter as
         flags.  Flags affecting 16550 operation and LSR/MSR interrupts
         must now be OR'd with the 'vctrnbr' argument of async_open
         rather than the 'combase' parameter.  ASYNC.DOC reflects these
         changes to the async_open function.




                             MCOMM 5.52 UPDATE NOTES

         No changes have been made to the serial code.  The video
         code includes a new feature that allows installing your own
         handler for unrecognized ANSI sequences (see SUPLMNT.DOC).
         The demos were updated to work with the latest versions of
         Borland/Turbo C/C++ and Microsoft C/C++.  The latest version
         of Zortech C/C++ the code has been tested with is 2.00.  They
         should work with later versions of ZTC with few or no changes.

         The ZMODEM demo (TXZM) was organized a little differently so
         all three supported compilers could use the the same ZMLIBs,
         rather than having a set of ZMLIBs for each memory model for
         each compiler.  This required including another module of the
         source code in the shareware version of MCOMM (XYZGEN.C) that
         formerly only came with the registered version.  This change
         also fixed some linker "unresolved external" errors for users
         of earlier versions of Turbo C.

         The TXZM demo now will respond with a CPR (cursor position
         report) sequence when it is sent an ANSI DSR (device status
         request).  This is so BBS systems that auto-detect ANSI will
         recognize TXZM's mini-terminal mode as an ANSI capable program.
         The implementation of this feature in TXZM is also a good
         example of how to put an unrecognized ANSI sequence handler in
         your program if you are using the MCOMM video functions.

         Support for "Doorway" mode was added to TXZM.  Pressing ALT=
         while in mini-terminal mode toggles this mode on and off.  The
         screen switches to a 25 line display when Doorway mode is on
         and reverts back to a 24 line display when Doorway mode is off.
         Since the purpose of Doorway mode is to allow the sending of
         special keys such as function keys, the arrow keys, PGUP, PDDN,
         etc., none of the TXZM program functions (including Exit, Help,
         Shell, etc.) work while Doorway mode is enabled.

         An otherwise undocumented -7 switch was added to TXZM.  This
         switch strips the high bit from incoming characters when in
         mini-terminal mode.




                             MCOMM 5.50 UPDATE NOTES

         Version 5.50 adds RTS flow control for the receive side.
         Previous versions supported monitoring CTS to insure the device
         being sent to was not overran but did not lower RTS if the PC
         was being overran.  The function 'async_msrflow' has been
         modified to support this option.  For more information, see the
         updated documentation on 'async_msrflow' in ASYNC.DOC.  This
         change also necessitated a change in the ASYNC structure making
         it one byte longer.  BE SURE TO USE THE RIGHT HEADER FILE AND
         RECOMPILE ANY CODE THAT USES COMM.H or COMM.HPP.

         Added a Zmodem demo program called TXZM.  The shell code and
         linkable libraries are not part of the shareware version of
         MCOMM.  Complete source comes with the registered version.
         This is primarily a demo with limited documentation and limited
         support.  It also happens to be very fast and contains a lot of
         extras.  It MAY NOT be distributed except as stated in its
         documentation.


                             MCOMM 5.41 UPDATE NOTES

         Version 5.41 contains a few minor changes and bug fixes.  These
         are:

         1) The 'volatile' keyword was added to ASYNC structure members
            that are modified by the interrupt handler.  This corrects
            problems with optimizing compilers (such as MSC 6.0) that
            load variables into registers.  Many of the macro
            implemented functions test variables that are modified by
            the interrupt handler.  If the compiler, in optimizing a
            loop, loads a variable into a register that is modified by
            the interrupt handler, it will never see the variable
            change.  The 'volatile' key word instructs the compiler to
            not assume the variable remains constant.  Thanks to Chris
            Fanning for pointing this out to me.

         2) The ANSI cursor position sequence did not recognize the
            window relative ('v_wrel') mode of operation.  If an ANSI
            cursor sequence was received, it was always treated relative
            to 0,0.  It now treats the current window's top left corner
            as 0,0 if 'v_wrel' is non-zero.  Thanks to David Speer for
            this information.