        RS232 - Asynchronous Communications Port Monitor - Version 2.03
        All Rights Reserved                                  23 Dec 1986

        RS232 is a memory resident program that displays RS-232 signals
        for com1 or com2.  It is intended to enhance internal modems by
        supplying software "lights" similar to those found on most
        external modems.

        Command Format:  RS232 [   | ? | 1 | 2 ]   where [ ... ] denotes a 
                                                   choice the following:
             blank - Displays this output before installed
                     Disables/enables display after installed
                 ? - Displays this output anytime
                 1 - Installs resident portion of RS232 for COM1
                 2 - Installs resident portion of rs232 for COM2

        No method of removing this program from memory has been
        implemented.  A boot is required.

        The output of this monitor program is displayed in the upper
        right hand corner of the display.  From left to right the meaning
        of the eight character display is:

                  T R R C R C T S
                  | | | | | | | |____ data (S)et ready
                  | | | | | | |______ data (T)erminal ready
                  | | | | | |________ (C)arrier detect
                  | | | | |__________ (R)ing indicate
                  | | | |____________ (C)lear to send
                  | | |______________ (R)equest to send
                  | |________________ (R)eceive data
                  |__________________ (T)ransmit data

        If any signal is off, its position will show a period.

        Compatibility:
        RS232 has been tested with IBM and Hercules monochrome and IBM
        color graphics video boards.  It has been used with an IBM EGA
        for a limited time with no ill effects.  Modems that have been
        tested with RS232 are Hayes 1200B, Hayes 300 and Ventel Half
        Card.  RS232 runs on the author's Fido node and causes no
        problems for the Fido software running on an IBM PC.

        Program limitations:
        The status bits used for Receive and Transmit Data get cleared
        too fast by the communication programs to be of much use.  Those
        signals therefore don't appear much of the time even though data
        is being received and transmitted.

        Update History:
        2.01 - April 86 - Original "working" version.
        2.02 - Aug   86 - Internal clean up.
        2.03 - Dec   86 - Fix lost characters when running with ProComm.
                          Added code to RS232 to send EOI to the 8259 
                          instead of waiting for int 8 to do it when 
                          RS232 iret'd from int 1Ch.
