RetroChallenge project completion

I assembled and debugged one channel of my vector generator, and wrote some of the firmware to drive it. I have unfortunately NOT finished building the second channel, though I got <fingers separation=”10mm”>this</fingers> close.

Would you believe <fingers separation=”20mm”>this</fingers> close?

I’m going to try to blame my not having made more progress on the local electronics store being closed today, so I wasn’t able to get a 74HC04 I need (or any other 74HC inverting gate). However, that’s a flimsy excuse since I should have anticipated the need for it, and I haven’t completely finished wiring the second channel.

I’m going to consider it a qualified success anyhow. Analog electronics isn’t really my forte, but I was able to analyze the operation of the original Ciarcia vector generator (“Make Your Next Peripheral a Real Eye Opener”, BYTE, November 1976, based on Hal Chamberlin’s earlier design published in the first three issues of The Computer Hobbyist, 1974-1975) to the point where I understand how it works, and was able to update the design in simple ways for construction with more modern ICs.  I did get one channel (half of a minimum vector generator) built and debugged, and test firmware written.

I also got Dave Kruglinski’s 8080 Space War game from the October 1977 BYTE  to assemble with a cross-assembler. As originally written, it used a point-plot display, rather than vector. I intended to modify it to talk to the vector generator but have not yet done that.


  1. Schematic
  2. Firmware source code (github repository)
  3. Photos
  4. Dave Kruglinski’s Space War source code (github repository)

I’d like to thank Richard Ottosen, Scot Anderson, and John Doran for advice and support on this project.

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