Bit of CP/M trivia needed - test-drb@ccmp.vtda.org

30 Aug 2005

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Subject: Re: Bit of CP/M trivia needed
   From: "Dwight K. Elvey" <dwight.elvey at amd.com>
   Date: Tue, 30 Aug 2005 10:14:15 -0700 (PDT)
     To: cctalk at classiccmp.org
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      I don't
think so. CPM was first written by Gary Kidall for the Intel
MDS-800 (go read the CPM docs) and they NEVER had DMA capability. They used
a 2k bit bootstrap loaded in a 1702 EPROM. Here is a picture of a MDS-800
with THE actual 1702 Boot EPROM 
Hi
 Yes, what I meant to say was for the S-100. I was told that the first
S-100 implementation used this type of board. I knew Gary used a
MDS-800.
Dwight 
No.  Most (if not all) of the first S100 system had front pannels 
(ALTAIR AND IMSAI Were the first!).  The few that didn't had some form 
of rom monitor to simulate a fronpannel via TTY such as Poly-88, 
Processor tech SOL and others.

I have the history of being Altair owner SN00200 an early one with a 
full set of warts and germs.  I was in the unenviable position by the end of
January 1975 of having an assembled and debugged machine with 4k and NO
software.  Needless to say I was very heads up for software of any kind. 

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><http://www.classiccmp.org/hp/mds-800/frnt-pan.jpg>. The 1702 is mapped
>into and out of the memory space by the BOOT switch on the MDS front panel.
>Allison's description is dead on.  
Should be with the hours spent using MDS800 and having one they are familiar.

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 >Dave Mabry is the expert of the Intel MDS
>and he can provide more details about how they're booted and the BIOS table
>is loaded. FWIW Gary had a contract to write PL/M for Intel and wrote CPM
>as a file handling system for use in developing PL/M. He offered Intel CPM
>but they didn't want it since they were working on their own OS.(BIG
>Mistake!) Intel's OS was released as ISIS and was only used in the Intel
>MDS systems (although I've heard they did have a PC version for a PC based
>MDS). ISIS is very crude compared to CPM.
>
>   MDS 800  <http://www.classiccmp.org/hp/mds-800/mds-800.htm>
>
>   You might also want to take a look at 'CP/M and a brief history lesson'
>here;  <http://www.classiccmp.org/hp/mds/mds.htm>. I used to have the exact
>quotes from Gary but unfortunately the link to them is now dead. 
Good synopsis.

Allison