Over on his blog our hacker [Scott Baker] restores a Prompt 80, which was a development system for the 8-bit Intel 8080 CPU.

[Scott] acquired this broken trainer on eBay and then set about restoring it. The trainer provides I/O for programming, probing, and debugging an attached CPU. The first problem discovered when opening the case is that the CPU board is missing. The original board was an 80/10 but [Scott] ended up installing a newer 80/10A board he scored for fifty bucks. Later he upgraded to an 80/10B which increased the RAM and added a multimodule slot.

[Scott] has some luck fixing the failed power supply by recapping some of the smaller electrolytic capacitors which were showing high ESR. Once he had the board installed and the power supply functional he was able to input his first assembly program: a Cylon LED program! Making artistic use of the LEDs attached to the parallel port. You can see the results in the video embedded below.

[Scott] then went all in and pared down a version of Forth which was “rommable” and got it down to 5KB of fig-forth plus 3KB of monitor leads to 8KB total, which fit in four 2716 chips on the 80/10B board.

To take the multimodule socket on the 80/10B for a spin [Scott] attached his SP0256A-AL2 speech multimodule and wrote two assembly language programs to say “Scott Was Here” and “This is an Intel Prompt 80 Computer”. You can hear the results in the embedded video.

Thanks to [BrendaEM] for writing in to let us know about [Scott]’s YouTube channel.