From: moskewicz AT MEM DOT po DOT com
Date: Sun, 26 May 1996 11:45:28 -0400
Message-Id: <9605261545.AA17295@mercury>
To: djgpp AT delorie DOT com
Subject: Re: COM port access

>Jamul <mhommel AT trumpet DOT aix DOT calpoly DOT edu>

>init_rs232(); (this is done with inline asm, using the "int"
instruction 
>  - is that bad?)
My impression is that, yes, it is generally bad, as AFAIK you are 
at the mercy of the DPMI host... use _dpmi_int type functions instead

>  So, the question of the day is, can anybody tell me what's going on 
>with this code?  It's been driving me insane for a good week, and I 
>suppose I can confide in you guys: it's due this friday!!  AUGH!  Well,
I 
>am going to give real mode turbo pascal a shot on tuesday if there
seems 
>to be no answer for DJGPP.  If it does the same thing, I will just
assume 
>I am much too dumb to program, and will retire.  That seems the most 
>reasonable course of action.
I would guess your program has a bug. :)
You might try to find a serial port library, I think one was uploaded to

delorie.com recently,  SVAsync v0.10 (obviously this is for djgpp 2.0).
But seriously, I suspect a sneaky, lurking bug. Like:

cmp $0, %%al
IS NOT
cmpb $0, %%al

This one irritated my for a while. Gas does not guess well. (Why should
it? :)
----
moskewicz AT mem DOT po DOT com