Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!samsung!olivea!tardis!jms
From: jms@tardis.Tymnet.COM (Joe Smith)
Newsgroups: comp.sys.m68k
Subject: Re: HELP HELP HELP on some Technical Questions for the 680000!!!
Summary: The Amiga *does* use 6800 compatible timer chips.
Message-ID: <1701@tardis.Tymnet.COM>
Date: 9 Apr 91 19:35:31 GMT
References: <1991Apr02.174845.5076@lynx.CS.ORST.EDU> <1991Apr2.220648.23079@colorado.edu>
Reply-To: jms@tardis.Tymnet.COM (Joe Smith)
Organization: BT Tymnet, San Jose, CA
Lines: 18

In article <1991Apr2.220648.23079@colorado.edu> rainer@boulder.Colorado.EDU (Rainer Malzbender) writes:
> ..., but I'm almost positive you don't have to worry about these signals
>at all if you're designing for the Amiga.

It's true that the expansion cards for the Amiga don't need to worry about
VPA, VMA, and E signals.  However, there are two CIA (Complex Interface
Adapters, with counters, timers, and 8-bit parallel I/O) on the Amiga's
motherboard that do need those signals.  Hardware hackers have already
found that simply doubling the CPU's clock does not work - the time-of-day
clock stops working, the floppy disk step-in/step-out signal stops working,
the parallel port stops working, the joystick and mouse stop working.
All because the E signal needs to be correct.

-- 
Joe Smith (408)922-6220 | SMTP: jms@tardis.tymnet.com or jms@gemini.tymnet.com
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