Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!cmcl2!pluto!avi
From: avi@pluto.dss.com (Avi Elenko)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Info wanted on 8253 chip
Summary: Mucking w/the Timer Tick interval
Message-ID: <4014@pluto.dss.com>
Date: 16 Aug 90 15:25:42 GMT
References: <570@esosun.UUCP>
Organization: Datability Software Systems, New York, NY
Lines: 29

In article <570@esosun.UUCP>, tanida@odin.css.gov (Tom Tanida) writes:
> I am writing an application which needs 100ths of a second accurate
> timing. Calls to the BIOS are not enough.  I have heard that accessing
> the 8253 timer chip is the way to go, but I cannot find any
> information on how to use the chip.  Can anybody out there let me know
> of a good reference/source of info for this?
> 
> Thanks,
> Tom

Tom -

    You can try the following assembly code.

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                     ; Program the 8254-2

    
    MOV AL,      24H ; Program high order
    OUT 43H,      AL ;
    MOV AL,       01 ; Once 100 micros
    OUT 40H,      AL ;
                     ;
    MOV AL,      14H ; Program low order
    OUT 43H,      AL ;
    MOV AL,     077H ;
    MOV 40H,      AL ;

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