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From: sac90286@uxa.cso.uiuc.edu
Newsgroups: comp.sys.ibm.pc
Subject: Interrupt Info Needed
Message-ID: <111700044@uxa.cso.uiuc.edu>
Date: 25 Feb 89 19:51:00 GMT
Lines: 23
Nf-ID: #N:uxa.cso.uiuc.edu:111700044:000:1219
Nf-From: uxa.cso.uiuc.edu!sac90286    Feb 25 13:51:00 1989


Can any of you kind netlanders recommend a good source of info on the PC
timers and interrupt controller? I need to perform some real-time data 
collection using an AT clone, and need the data points to be collected at
precisely-spaced intervals. I am attempting to generate some code to
	1) program the on-board timer chip to count down at a specified
frequency, and once it has counted down to generate an interrupt,
	2) write a handler to process this timer-generated interrupt which
initiates the data read sequence,
	3) write another handler to process the "data ready" interrupt which
is generated on the analog input board when the data is valid and ready to be
read by the computer, which is on IRQ7.

I have consulted Norton's Programmer's Reference to the IBM PC as well as the
AT Tech Ref. Manual, but both seem to gloss over the detailed specifics I need
in order to accomplish the things outlined above. 

Anyone know of a good, thorough, and very deatiled book on the subject which
doesn't cost $500? I'd also be quite happy to look at some source code, if
anyone would care to email me some (the board in question is the IBM DACA
board, if anyone's interested). Much obliged!

sac90286@uxa.cso.uiuc.edu