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From: axaris@acsu.buffalo.edu (vassilios e axaris)
Newsgroups: comp.os.msdos.programmer
Subject: debugging ISRs
Message-ID: <32203@eerie.acsu.Buffalo.EDU>
Date: 6 Aug 90 22:29:41 GMT
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Hello,

I have written a com1 isr which doesn't seem to work eventhough it is rather
simple. I use MSC 6.0 and after going carefully through the 8250's manual for
initialization values, I cannot get the damned thing to work. I am testing it
by transmitting a value from com2 and use global vars to store the incoming
data. But, no dice! :-( All the declarations are correct, everything in order.
Is there a way to trace what's going on?
My settings are: 9600 baud, 8 bits, 1 stop bit, no parity. I noticed one thing 
so far: the status as returned by _bios_serialcomm (used only for initializati-
on) is different during different runs. But the important bits are properly 
set, ie: break, frame error, time out, overrun, e.t.c.
Any suggestions will be greatly appreciated.

Vassilios E. Axaris