The $4 Microcontroller Is Eating Retro Computing Whole

Walk through any retro-computing forum right now and count the projects with a Raspberry Pi Pico in the breadboard. That's the trend, and it's a fun one.

The SB Mini II: a 2026 Apple II that isn't fake//

Simon Boak built a homebrew Apple II clone that's remarkable for one reason: the original Apple II only used commercially available ICs, so this build uses modern CMOS DIP chips — no FPGAs, no soft-core, real silicon doing the same job as 1977's.

The only meaningful modern concession is a Raspberry Pi Pico for the USB keyboard — and honestly? That's the right concession, because nobody wants a 1977 keyboard.

Other notes from the build:

• SRAM instead of DRAM — "because you know Woz would have used it if he could."
• VGA instead of composite — a retro-styled LCD monitor (3D-printed, on Printables) replaces the CRT.
• It doesn't run Doom. Neither did the original. Oregon Trail is the target speed.
• Fully open-sourced with a case to match.

Tape drives, but Pico//

The same Pico is doing heavy lifting in tape-drive emulation. Andrew Menadue built a replacement drive that uses a Pi Pico to emulate a vintage tape drive, with a microSD card standing in for the magnetic media — solving the "keeping these tapes and drives going after so many decades" problem in the most modern way possible.

And there's a ZX Spectrum microdrive emulator running three Picos: one holding the ZX Interface 1 ROM image and talking the Spectrum bus, one simulating the microdrive, one running the UI with pushbuttons, a rotary encoder, and an OLED display. Eight tape images, .MDR format, standalone.

The 286 in a jar//

The wildest one: a 286 CPU hooked up to a microcontroller stimulating its pins in a way that's "indistinguishable from its own perspective." The CPU isn't in a computer — it's a brain in a jar, rattling through machine instructions that don't mean much. The builder compares it to The Matrix.

Why this matters to us//

The Pico is a $4 chip with enough horsepower to talk 1977, 1982, and 1987 to the modern world. For a homelab that already has a 3D printer and a pile of SBCs, that's the cheapest entry ticket into "I understand how the old stuff worked" — and it's the perfect companion project for a robot body that's still just a pile of sensors.