Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!caen!zug.csmil.umich.edu!chymes
From: chymes@zug.csmil.umich.edu (Charles Hymes)
Newsgroups: comp.sys.amiga.hardware
Subject: I'm replacing a CMOS chip with an nMOS chip. Should I worry?
Message-ID: <1991Mar10.184945.14146@engin.umich.edu>
Date: 10 Mar 91 18:49:45 GMT
Sender: news@engin.umich.edu (CAEN Netnews)
Organization: Cognitive Science Machine Intelligence Laboratory, U of M.
Lines: 17

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The PD I/O expantion board I just built dosent work, and the current
thing to try is to replace the chips. The board uses a R65C22p1 CMOS
VIA, a R65c52p1 CMOS DCIA and a MC4F139 IC.
I've gotton ahold of a number of R6522p nMOS chips, and I'm going to replace
the CMOS R65C22p1 with it. The only difference I can see is the power
disipation. The CMOS chip is rated at 7-10 mW/Mhz and the nMOS chip is
rated at 450-700 mW.
Does this make them incompatable?

Also, I'm going to try and replace the MC74F139 with chips lables
74LS139. The difference being LS vs F.  I think LS means low poew
Shottsky, but what does F mean, and can I interchange the chips?


Thanks for the info,
Charles