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From: rainer@hibachi.colorado.edu (Rainer Malzbender)
Newsgroups: comp.sys.m68k
Subject: Is 68000 E signal a good clock ?
Message-ID: <24775@boulder.Colorado.EDU>
Date: 15 Aug 90 05:15:07 GMT
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Reply-To: rainer@hibachi.colorado.edu (Rainer Malzbender)
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Sorry, this is a real RTFM question, but the manuals I have are unclear.
I'm currently hacking a 68008 with a 10 Mhz clock, and I'm feeding an 8254
with the same clock. Well, the rub is, it's late at night and I only have
an 8253, which will only accept clocks to 2 Mhz. So my brilliant idea is
to temporarily use the E pin, which is advertised to be CPU clock/10.
Having fortunately avoided 6800 peripherals and micros so far, I know little
about this signal. Is it in fact just the CPU clock divided down, or does
it do squirrely things when wait states or interrupts happen ? I need it
to be rock solid.

Thanks for all the fish, er, help.
--
Rainer M. Malzbender                          Technology recapitulates biology.
Dept. of Physics                (303)492-6829       rainer@hibachi.colorado.edu 
U. of Colorado, Boulder, USA                  malzbender%opus@vaxf.colorado.edu