CP/M/CPM_CDROM.iso/cpm/turbopas/comdemo.ark/COMDEMO.DOC

Text File | 1986-08-24 | 6KB | 122 lines

          COMDEMO.PAS - A TURBO PASCAL COMMUNICATIONS DEMONSTRATION

Introduction

  COMDEMO.PAS  is a demonstration of communications using Turbo Pascal.  It
uses a proposed standard library of communications library of routines that
can be implemented for a variety of microcomputers.  COMDEMO.PAS will allow
a connection to a remote computer via a communcations port.  It  will  also
allow file transfer of ASCII files between the two computers.

  COMDEMO.PAS  was  written  as  a 'test- case' for CLIB180.INC - it's also
useful as the 'first piece' to customize a 'text-capture' utility for a new
micro system, which doesn't yet have  a  way  to  'talk  protocol'.   Turbo
Pascal's  inherent  compilation  speed and relatively high portability will
help in getting the first and  crucial  step  accomplished  :  enable  text
capture  to and from another system.  The typical next step is to establish
an error correcting protocol like Kermit.

  Further  information  is available from 'CLIB180.INC', 'CLIB180.DOC', and
the source of this program 'COMDEMO.PAS'.

  COMDEMO.PAS  makes heavy use of the standard communications library.  All
character I/O is done through the library functions, and disk I/O  is  done
through  standard  Turbo functions.  This program should run on most micro-
computers that are supported by Turbo Pascal  without  modification,  if  a
similar set of library functions are implemented for it.

  This  program  was  written  by  Jeff  Duncan, with considerable help and
advise from Bernie Eiben.  Comments, suggestions, etc, are welcome.  I  can
be   reached   at   (617)   839-5673   (evenings)   or   send  comments  to
LSM>DUNCAN@DEC-MARLBORO (preferable).

Installation

  Unless the user obtains a compiled copy of COMDEMO.PAS for his system, it
must  be  installed  and  compiled.   The  following  is  the  installation
procedure for the program.

  1.  Obtain a copy of COMDEMO.PAS and the communications library include
      file for your system.

  2.  Rename the include file 'COMMLIB.INC'.

  3.  Compile COMDEMO.PAS to disk.

  4.  Installation complete.

Operation

  When  COMDEMO.PAS  is run, the message : *** Connected to remote port ***
is printed on the console.  At this point, all characters displayed on  the
screen   are   characters  received  from  the  communications  port.   Any
characters typed at the console are sent out the communications port.  This
creates a virtual terminal connection to a remote system.

  Also  printed  is  a  menu  of  commands  possible  for COMDEMO.  All are
prefixed with Control-backslash.  All commands may be in upper case,  lower
case,  or  the  control representation of the character.  The following are
the possible commands:

    B- Set  the baud rate.  A list of possible baud rates is displayed and
       the user is prompted to type the number of the  desired  baud  rate.
       The  program  reports  the  success or failure of the operation, and
       reconnects to the communications port.

    D- Set  carriage  return  delay.   This will allow the user to set the
       delay after each carriage return is sent during  a  send  operation.
       The  default  delay  is  0,  and the actual value of delay is system
       dependent.  Maximum value for the delay  variable  is  32767.   This
       will  help  when sending to a system that requires a delay, and will
       also help by allowing a slow echoing system time to catch up and not
       overflow the computer's input buffer.  On a VT180,  numbers  in  the
       100's  will  give  a  reasonable delay as the delay is approximately
       5ms/unit.

    E- Exit program.  Any open log files will be closed.

    H- Redisplay menu.

    P- Set the communications port.  A list of possible ports is displayed
       and  the  user  is  prompted to type the number of the desired port.
       The program reports the success or failure  of  the  operation,  and
       reconnects to the communications port.

    Q- Exit program.  Any open log files will be closed.

    R- Receive  a  file.   A prompt will be given for a filename, and that
       file will be opened.  Warning, this is a destructive open, no  check
       is  done for an existing filename.  All characters received from the
       communications port will be saved in a log buffer.  When logging  is
       complete,  either  ^\-W,  or an exit command will close the log file
       and save it to disk.  The size of the log buffer is 32k, so on small
       systems this program must be compiled to disk.  The size of the  log
       buffer is set by the constant 'maxbuffer'.  Fortunately, the size of
       the  log buffer does not affect the size of the compiled program, at
       least under CP/M, so any size  may  be  used  provided  it  fits  in
       memory.

    S- Send  a file.  A prompt will be given for a filename, and that file
       will be sent via the communications port to the remote system.   All
       lines  will  be  terminated  with  a  carriage  return  only  to  be
       compatible with typical  editors  and  text  capture  mechanisms  of
       computers.   At  the  end  of  the  file  transfer, the file will be
       closed.  All characters received during the file  transfer  will  be
       displayed  on  the  screen.   Typing  any  character  will abort the
       operation.

    W- Write  currently  logged  data,  and  close the log file.  All data
       accumulated will be saved in the open file, if one  were  opened  at
       the  time.  No warning is given if a file was not opened, or no data
       was accumulated.

System Dependent Code

  There  should  be  no  system  dependent  code in the program, except, of
course,  the  communications  library.   The  program  sets   the   default
communications port, baud rate, and parity as defined in the communications
library.   Other  ports  and  baud  rates  may  be set after the program is
started by using the ^\-B and ^\-P commands.