Early Microprocessors in Industrial Microcomputers

Pete Lancashire pete at petelancashire.com
Wed Mar 9 21:27:19 CST 2016

Had my numbers mixed PLC-2 family 1772-M8 and -M16

Pretty bad since one is about 20 feet away from me


On Wed, Mar 9, 2016 at 6:20 PM, Jon Elson <elson at pico-systems.com> wrote:

> On 03/09/2016 11:30 AM, Pete Lancashire wrote:
>> Before uP's many used bit slice's I'm slowly putting together a
>> Westinghouse Numa-Logic 700 and 1200 setup. (BTW anyone have parts,
>> software, etc ?).
>> In my opinion Modicom was the best, did not need external cooling, A/B has
>> clout thus pretty much dominated. Did you know they used core at first and
>> some customers demanded it since it kept its ones and zeros when the power
>> went away ?
> As far as I know, the 7300 never used core.  No sign of anything like that
> in the book.  They did have a big backup battery for the DRAM, I used a
> couple AH 12 V Gel Cell battery.  The charger for the Gel Cell ran when the
> control power was off, so it was supposed to maintain the memory
> indefinitely - except the memory power switch had a dirty contact and would
> dump the memory every couple of weeks.
> Jon

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