Newsgroups: comp.sys.ibm.pc
Path: utzoo!utgpu!jarvis.csri.toronto.edu!csri.toronto.edu!il
From: il@csri.toronto.edu (Indra Laksono)
Subject: Re: Com: --> Disk
Message-ID: <8901061108.AA11316@ellesmere.csri.toronto.edu>
Organization: University of Toronto, CSRI
References: <126@csd4.milw.wisc.edu> <742@optilink.UUCP>
Distribution: na
Date: Fri, 6 Jan 89 06:08:39 EST


In article <742@optilink.UUCP> writes:
>In article <126@csd4.milw.wisc.edu>, burkett@csd4.milw.wisc.edu (Edward W Burkett) writes:
>> 
>> I recently picked up a copy of a program called LPTx which is a TSR
>> package that redirects output from 3 printer ports to 3 files.  It is
>> a great program and is available from Simtel.
>> 
>> What I want to know is ---- Can the same thing be done with a serial port?
....
>Redirecting the BIOS interrupt for serial I/O is not a hopeless task --
>the sources for LPTX are supposed to be distributed with the .EXE --
>so you might be able to use that as an example of how to do it -- but
>this is likely to be useful in only a few cases.
>

Clayton is right.  I know of no commercial program that writes
to the COM ports by BIOS or DOS.  They are not interrupt driven!

There is a neat little solution, if you have two serial ports,
get a null modem cable (straight through, but pins 2 & 3 crossed).

Then write an ISR that writes every character arriving at the second
serial port to disk.  The code will be even simpler than LPTX



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Indra Laksono                                 ----    ---,
University of Toronto, Canada M5S 1A4          `'        |
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