Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cmcl2!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.sys.apple
Subject: Re: 10 mhz chips
Message-ID: <11591@smoke.BRL.MIL>
Date: 13 Nov 89 22:55:52 GMT
References: <2473.cortland.info-apple@pro-houston> <36403@apple.Apple.COM>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 16

In article <36403@apple.Apple.COM> mattd@Apple.COM (Matt Deatherage) writes:
>Faster video is one thing, but faster I/O could very well mean that none of the
>existing peripheral cards for the Apple II would work in such a new IIgs.  Do 
>you think all people who would want a new IIgs would be ready to give up their
>5.25" disk cards, their Video Overlay cards, their FPE cards, maybe their
>TransWarp cards, their parallel printer cards, their slot-based RAM cards,
>their IEEE-488 cards, and who knows what else?  I have my doubts.

There is precedent here.  Remember the Apple //c subfamily; it might as
well have had much faster I/O capabilities since they were all onboard.
In fact the IIGS basic I/O support is all onboard, so slots could run
at any arbitrary speed just so long as slot card firmware made no
assumptions about CPU cycle rate.  A bus line containing a universal
reference oscillator tap (e.g. 1MHz, to pick a random number) would
be better for such cards to use when they really needed an external
timing reference.