PICO-56 coming soon!

A project log for HBC-56: 65C02 + TMS9918A on a backplane

HBC-56 A homebrew 8-bit computer with a backplane. Initially with a 65C02 CPU card, a TMS9918A VDP and dual AY-3-8910 audio.

troy-schrapelTroy Schrapel 10/26/2023 at 05:253 Comments

The complete HBC-56 (65C02/TMS9918A/AY-3-8910) homebrew CPU now emulated on a $4 Raspberry Pi Pico. Project details coming soon: Here's a sneak peek at the new PCBs


adam.klotblixt wrote 10/26/2023 at 11:43 point

Nice! The Pico really is something. A great opportunity with this is the possibility to do small changes, like having more than 4 sprites per line :D

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Troy Schrapel wrote 10/26/2023 at 22:26 point

Absolutely! That actually leads into my next project. I'll be attempting to create a drop-in replacement for the TMS9918A using a Pi Pico (eventually a custom RP2040 board). Similar to the awesome F18A project, but using an MCU instead of FPGA. I'm 90% confident it can be done.

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adam.klotblixt wrote 10/27/2023 at 04:43 point

There is something similar already brewing, take a look at
But I guess you refer to making a physical chip drop-in replacement, which is awesome for all the vintage computers and consoles :D

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