Path: utzoo!attcan!uunet!ogicse!ucsd!ucbvax!NISC.SRI.COM!bjork
From: bjork@NISC.SRI.COM (Steve Bjork)
Newsgroups: sci.electronics
Subject: Re: AMD 8251 (USART) Info?
Message-ID: <23469@fs2.NISC.SRI.COM>
Date: 14 Nov 90 17:15:51 GMT
References: <60822@bbn.BBN.COM>
Reply-To: bjork@NISC.SRI.COM (Steve Bjork)
Organization: Network Info Systems Ctr., SRI Intl., Menlo Park, CA.
Lines: 13

In article <60822@bbn.BBN.COM> gonzalez@vax.bbn.com (Jim Gonzalez) writes:

>working on a Cromemco System Three (S-100 bus with a Z-80).  The CPU board
>apparently produces a 4MHz clock, while the serial board expects to be 

The CPU chip is clocked at 4 or 2 mhz, depending on the switch setting
on the ZPU. There is a constant two megahertz clock available on bus
(pin 49 or so). I've cut the trace from the middle of the board and run
wires to this pin on Many IMSAI SIO-2's to run them in a ZPU system.

So, just get the knife and soldering iron out, and Hack!

--Steven