Date: Mon, 31 Jan 2000 09:30:25 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: pwillard <pwillard AT mediaone DOT net>
cc: djgpp AT delorie DOT com
Subject: Re: I need to advice on timing...
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On Mon, 31 Jan 2000, pwillard wrote:

>     I need to touch external hardware through the parallel port and so far,
> doing that hasn't been a problem.  Now, I need  to control the timing of
> signals sent to the external hardware.  I can sucessfully create a 50
> millisecond pulse using the 8259 clock stuff, but I have no clue how to
> generate a shorter than 1 millisecond signal.  I now need a 10, and a 50
> MICROSECOND signal and I'm not sure if I can.... IS it possible?

You could read the timer counter (it runs at sub-1 microsecond
resolution).

If that isn't good enough, I think your best bet would be to find a
loop that takes 50 microseconds to execute, and use that loop when you
need to toggle that bit.

In general, timing devices on a PC are just not reliable enough for
such short periods of time.  So you will need to experiment to find
the way that works for your application.