Date   : Wed, 27 Dec 1989 01:01:44 GMT
From   : portal!cup.portal.com!Jhanos@uunet.uu.net (JONATHAN E HAWES)
Subject: CLOCK/CALENDAR FOR CP/M

Greetings,
 
Again I address this thread to ask if there is anyone who knows of the
things I have been reading about. This past weekend I was reading over
some back issues of MicroCornucopia, and two articles came immediately
to my attention.
 
     1 - First was the article by Mitchell Mlinar about the building
         of a hardware clock for the Xerox 820-II.(MicroC, Oct '84)
         In the article, he describes this clock circuit and how it
         plugs into the Parallel printer port on the motherboard.
         Now, since I have a BBS operating on a Xerox 820-II, and
         seeing how I don't have an adequate way keep a battery back-
         up clock, I tried assembling the parts for this device.
         Unfortunately, I can't seem to find the 18 pin clock chip
         described in the article. Mitch asks for a MSM5832 clock/
          calendar chip. Well.... having called all over the nation
          looking for one, I still can't seem to find one. Is there
          source for these, or is their a modification to allow the use
          either the 24 pin or 16 pin clock chips from National Semi-
          conductor. I figure the schematic has been modified over the
          years, but surely someone out there knows how to build one,
          and would be willing to explain it to this ingnorant sysop.
  
      2 - The other article that caught my eye was from the April '84
          issue, that being an evaluation by Clarence Peckham of the
          Xerox 820-II and the LA Software Dynadisk, a 256k RAM array.
          Is there anyone out there who remembers these things?
  
          { Dang! asking like that makes me feel ancient! )
  
Any help will be greatly appreciated, and muchly welcomed! :)
Jonathan Hawes