I have a hankering to build a simple integer BASIC Atom clone toy, in the spirit of Grant Searle's verboard Jupiter Ace or Tynemouth Software's Minstrel ZX80 Clone. I would like to keep the design somewhat period, so no ICs newer than 1985.
I looked at the 202,000/C schematic and to make it simpler, conceptually it looks like we could:
- Eliminate the bus drivers on the edge connector
- Eliminate the printer port and VIA
- Replace the dual 2114 SRAM banks with a pair of 6264 SRAMs and simplify the address decoding
- Implement Component Video Colour output as per Hoglet's Transistor video driver
Then it dawned on me that in the past 40 years, someone might have done this before, especially integrating things like the video fix which I am still wrestling with. I found
But this actually seems more complicated, so wondered if anyone knew other builds more on the lean side - even better if there was a final schematic?