21MX proms (per request

dwight dkelvey at hotmail.com
Thu Sep 10 09:14:53 CDT 2015


Anyone interested in doing 1702As should look at the schematic
in the MCS4 user manual on bitsavers.org
There is a schematic for a MP7-03 board. It can be easily controlled
from an Arduino or raspberry pi. There are a few oneshots but those
can easily be replaced by software. You mainly need the level converters.
Dwight

 
From: dkelvey at hotmail.com
To: cctalk at classiccmp.org
Subject: RE: 21MX proms (per request
Date: Thu, 10 Sep 2015 07:03:53 -0700




I would be surprised if it did 1702s and 2708s. Even 2716s have
a slightly different hardware configuration.
1702s require voltages like 50 volts ( I could be a little off ) and
changing address and data lines over wide voltage ranges.
2708s require multiple rail voltages as well as programming voltages.
2716 are that last of the program by turning the programming voltage
on and off.
All the newer chips have a constant programming voltage and
a separate program logic level pin. They can even be read while
the programming voltage is high.
I doubt any would make the special provisions for 1702s. 2708s
are a stretch but if your not doing 2716s it won't be able to
handle 2708 even if it had the extra rail voltages. 
I have a DataIO ( I think a 29B ) and I know it doesn't do 1702s.
In any case, I don't think any of these would be fast enough for
a 21MX boot code. I think these expect it to be faster than 100ns.
Dwight
 
 		 	   		   		 	   		  


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