Article View: comp.os.msdos.programmer
Article #4021Re: Fixed clock speed on pc? CLK_TCK == 18.2 is TRUE??
From: Jeremy J Starcher
Date: Sat, 22 Dec 1990 04:24
Date: Sat, 22 Dec 1990 04:24
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1740 bytes
In article <2972@pensoft.UUCP> lwb@pensoft.UUCP (Lance Bledsoe) writes: >In article <15779.2770e40e@levels.sait.edu.au> marwk@levels.sait.edu.au writes: [ Question Deleted] >Thats correct! The clock inturrupt on ANY PC/AT/XT/CloneT is envoked exactly >every 18.2 times a second. > Watch out! The normal clockspeed is about 18.2 times a second. Some programs (GWBASIC) change the clockspeed (thus the clock interrupt) to four times that speed. GWBASIC sets up a new handler (INT 8h I think) to call the old one once every four ticks. Although this won't matter to most programs, in a few weird situations it could be nastly. I know, a minor quip since most people will never care about it. However being a low-level programmer makes me very carefull to document any possible side effects of a feature or function. PS--- I don't know if that modified clockspeed is a constant state or weather that only comes in when music is playing... -- --------------------------+--------------------------------------------------- Jeremy J Starcher ! No programmer programs in LOGO after reaching r3jjs@vax1.cc.uakron.edu ! age 14... r3jjs@akronvm.bitnet !
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arc1-ca.pugleaf.net!utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!VAX1.CC.UAKRON.EDU!r3jjsReferences:
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Path: arc1-ca.pugleaf.net!utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!VAX1.CC.UAKRON.EDU!r3jjs From: r3jjs@VAX1.CC.UAKRON.EDU (Jeremy J Starcher) Newsgroups: comp.os.msdos.programmer Subject: Re: Fixed clock speed on pc? CLK_TCK == 18.2 is TRUE?? Message-ID: <923@VAX1.CC.UAKRON.EDU> Date: 22 Dec 90 04:24:52 GMT References: <15779.2770e40e@levels.sait.edu.au> <2972@pensoft.UUCP> Reply-To: r3jjs@VAX1.CC.UAKRON.EDU (Jeremy J Starcher) Organization: U of Akron Computer Center, Ohio Lines: 28