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From: testurm@immd4.informatik.uni-erlangen.de (Torsten Sturm)
Subject: Re: Looking for a COM DLL (or DDE)
Message-ID: <1991Jun28.162933.1337@informatik.uni-erlangen.de>
Organization: CSD., University of Erlangen, Germany
References: <1991Jun26.204757.19291@cbnews.cb.att.com> <29426@uflorida.cis.ufl.EDU>
Date: Fri, 28 Jun 1991 16:29:33 GMT
Lines: 24

hans@pine.circa.ufl.edu (Hans van Oostrom) writes:

>A TSR is definitly not the way to go.  Windows has interrupt driven 
>serial I/O drivers build in, and they work pretty good if you don't do 


It is not true, that the comm.drv is real interrupt driver commdriver.

I have the source code of it.

If you call writecomm(), windows make a while-loop, calling for 
each (!) character in the buffer a call to the driverfunction
$SNDCOMM. This is not what I would call an interrupt-driven way to
send characters. This is additionally the reason, why you cannot run
at high baud rates.

Torsten.
---
Torsten Sturm 
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