I got another message from @x48x4b regarding his Microprofessor and the Sargon chess program; he writes: 

"This is my machine from the 1980ies, in today's working condition: https://www.mycloud.ch/s/S00E8C2E8289DDE0E50B95028DFF9DB989ABBE58C10 It is an MPF-IP with the stock accessory boards IOM-MPF-IP and EPB-MPF-IP and 16k RAM. On the bread board section, I have installed an additional PIO, 4 motor drivers and 2 A/D converters. This was done in the 1980ies, to be used withe my Fischertechnik robot. Today, the accessory boards can occasionally be found on Ebay. The Sargon code for my MPF-IP is here: https://www.mycloud.ch/s/S007B47874D00053B738BFE0EA9720BCA96DFA769F "

I take the freedom to post hist machine here - what a setup!! A dream Microprofessor: