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Old 7th May 2021, 8:43 am   #57
TonyDuell
Dekatron
 
Join Date: Jun 2015
Location: Biggin Hill, London, UK.
Posts: 5,191
Default Re: Early EPROM programmer.

Actually, not just the schematics on that site came from me (you're right, that is my handwriting). The photos are mine too, of the EP4000 and P4000 that I own. And I am pretty sure the dumps are of the firmware in my units. It was easier for me to point you to that site and you get higher resolution photos anyway.

Both units have internal power supplies and they're not simple. I am sure the Softy-2 supply was a lot less complex. The DIN sockets on the EP4000 are indeed composite video (pin 2 ground, all other pins in parallel carrying composite video) and cassette/RS232 (ground on 2, cassette in/out on 1 and 3, RS232 in and out on 4 and 5)

I did indeed mean that the P4000 would most likely now be raided for 8154s (and maybe the SC/MP). But you can be assured that mine remains -- and will remain -- complete and working.
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