From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Jump from timer interrupt?
Date:	8 Jun 2003 19:08:56 GMT
Organization:	Aachen University of Technology (RWTH)
Lines:	21
Message-ID:	<bc01k8$mpg$1@nets3.rz.RWTH-Aachen.DE>
References:	<MAPI DOT Id DOT 0016 DOT 00333138303633303030303930303110 AT MAPI DOT to DOT RFC822>
NNTP-Posting-Host:	acp3bf.physik.rwth-aachen.de
X-Trace:	nets3.rz.RWTH-Aachen.DE 1055099336 23344 137.226.32.75 (8 Jun 2003 19:08:56 GMT)
X-Complaints-To:	abuse AT rwth-aachen DOT de
NNTP-Posting-Date:	8 Jun 2003 19:08:56 GMT
Originator:	broeker@
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

Erik Berglund <erik2 DOT berglund AT telia DOT com> wrote:

> I am writing a music sequencer program for DOS using djgpp 2.01
> and gcc 2.7.2.1, 

Those quite old versions.  You may want to update your tools once in a
while...

> the sequencer. Is it possible to jump from my interrupt routine
> to the PC timer interrupt once in a while, to update the PC clock
> at 18.2 Hz? 

Yes, but it may be a bit hard to do from C code.  You may have to use
(inline) assembler for that.  At minimum, you'll need a protected mode
wrapper around the real-mode interrupt handler so you can call it from
compiled C code.


-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

- Raw text -