Kleincomputer KC 85/3: Part 1 (First look)

Subscribers:
3,270
Published on ● Video Link: https://www.youtube.com/watch?v=chH5ZGTi4YU



Duration: 23:20
1,274 views
60


Let's have a look at the East German (DDR/GDR) Robotron KC 85 "small computer" that runs on the East German Z80 clone called the U880 - in this case it's the UB880 variant.

A lot of excellent information ... and photos ... can be found here:
https://floooh.github.io/virtualkc/p010_kc85.html

The keyboard connects via a mono 3.5mm plug and reminds me of a calculator keypad. Opening it up shows a lot of different layers ... yikes ... looks like a real PITA (pain-in-the-aß) to re-assemble. Yay.

I finally found what the "U807D" chip is in the keyboard:
https://oldcomputer.info/8bit/kc85_3/index.htm

The "basis device" or main unit is pretty solidly built. The mixture of English and German seems a bit weird. This KC85/3 comes 16KByte of main RAM, 16KByte of video RAM, 8KByte of ROM and includes 8KByte of BASIC built-in. The previous KC85/2 doesn't have BASIC built-in.

This example also includes a 64KByte RAM expansion (8 x 64Kbit) ... I don't know if this replaces the internal 16KByte of RAM or adds to it (80KByte in total).

It has a single expansion interface and a 2x13 pin edge connector for the TV-RGB output (not sure if Soviet 2.5mm pitch or Western 2.54mm/0.1" pitch). So I'll need to do some research on creating a cable for video output.

Schematics can be found here:
http://www.mpm-kc85.de/schaltbild/KC85_3_Grundgeraet_sp.pdf







Tags:
kc 85
gdr
ddr
kc85
klein computer
kc85/3
kc85/2
kc 85/2