VOGONS


First post, by coolgenie

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Recently I noticed a PC/AT-class emulator running on Pi Pico boards (PCB “Murmulator”). Since Waveshare now sells a compact RP2350B-PiZero board with built-in HDMI output, microSD, and two USB-C ports, I decided to port the emulator to that platform.

So far I’ve:

  • Fixed HDMI timing on the Waveshare board
  • Improved the VGA emulation
  • Increased text-mode rendering to use a proper 8×16 font (much nicer readability)
  • Added USB keyboard and mouse support
  • In terms of speed, it feels roughly in the range of a 286 to a 386SX .

If you want to try it, the source is on GitHub: https://github.com/petr-to/pico-286-waveshare

Why Waveshare / what’s next
The original motivation was RP2350B’s higher GPIO count versus the “usual” small boards. My longer-term goal is to turn this into a kind of modern SBC with a real 8088 connected over GPIO: code would execute on the real Intel CPU, while the RP2350-based “mainboard” would provide RAM, video, keyboard, and storage.

I’m also considering ISA support. With enough GPIOs (and some multiplexing), it might be feasible to expose an ISA slot (or at least a subset) for experiments.

Alternative direction: modular “plug-in” architecture
Since PC/XT isn’t exactly a hot topic nowadays, and getting a 386/486-class CPU running at a decent speed on a small, affordable board isn’t trivial, I’m considering a more flexible modular design:

  • One Pico 2 (or similar) as a “mainboard” handling CPU (286/386SX class) plus ~8 MB RAM
  • A second Pico 2 dedicated to VGA emulation with higher resolutions / more colors
  • Optionally a Teensy 4.1 as a “performance module” (e.g., CPU+memory emulation targeting 386DX, maybe even 486SX territory)

What do you think—does the “real 8088 over GPIO” direction sound interesting to you, or would the modular multi-MCU approach be more useful/practical for this community?

Reply 1 of 3, by igully

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I am all for reusing one of these sub $20 boards (with built-in MDA video, Conventional RAM, SD card as storage and USB for keyboard and mouse) for an 8088 XT PC-like design. As long as it only does require flashing a provided firmware and that is it. Simplicity and ease of fabrication are generally lacking. There are many projects already out there that become a puzzle for non DIY builders. With soldering involved, even SMD components, extra custom PCBs, and weird toolchains to build their firmware. That for me is a big no.

That said, it is understandable that if the user wants more features, like extra RAM, faster CPU, etc. then the complexity should start to rise and so the skillset required to assemble it. The plug-in idea sounds interesting, but would probably cover more uses by implementing it in already accepted standards like ISA. That would open up the door for reusing these expansions on vintage hardware as well.

My two cents.

Reply 2 of 3, by theelf

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Hi! this look amazing, i want to test

I just need to buy this one true? https://www.amazon.es/Waveshare-RP2350-PiZero … r/dp/B0FGH8KNB2

I want to use a HDMI>VGA to use in a CRT, someone tested? i read proper HDMI resolution 640x480@60p ? the proyect have a fixed resolution? or dinamic ones?

thanks a lot

Reply 3 of 3, by coolgenie

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Yes, that is a correct board. Resolution is fixed.