Colin MK I

Early developments

System developments
After a few months of writing small assembly language programs in HEX and saving them to cassette, I got somewhat bored and wanted to progess to some real programs. Hand coding wasn't a problem, as that was how I wrote short diagnostic programs for the process control computers I worked on, but I wanted more!!

Having decided I knew enough to start designing my own parts for the computer, the most obvious expansion was going to be memory.


The first card I designed and built was a 128kB dynamic RAM card.

Following on from my runaway success with designing and building the 128K DRAM card, I followed up with following designs:

  • Dual channel RS232 card
  • Stereo sound card with speech synthesis
  • 64k static RAM card

More photos of Colin MK I
Below are a few pictures of the updates to Colin MK I, including some of my original design drawings.

All of the new cards I designed were built on Veroboard with wire wrap sockets. All hand wired by me!

Viewing the gallery
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