June 5, 2026
Old chip, new tricks, big side-eye
Watching a Z80 from an RP2350
Geek tries to make a tiny modern chip spy on a vintage computer — commenters ask why bother
TLDR: Kevin is testing whether a tiny modern controller can monitor a classic Z80 computer chip, including how slowly that old chip can be clocked. The big community reaction so far is skeptical curiosity: neat project, sure, but commenters want to know what it’s actually for and why it matters.
A hobbyist on Kevin’s Blog is trying to get a modern Raspberry Pi Pico-style board to watch what an old-school Z80 computer chip is doing in real time — basically, pairing a pocket-sized modern brain with a retro legend from the 1970s. The project is still in its early “can I even see what’s happening?” phase, with Kevin testing whether the newer board can read the Z80’s address lines, data lines, and clock timing without breaking anything. It’s niche, nerdy, and exactly the kind of thing retro-computing fans adore.
But in the comments, the real plot twist arrived fast: “Cool, but… why?” One reader, tetris11, became the voice of the skeptical crowd, asking the question that always lights up hobby-tech discussions: is connecting two chips together really that hard, or is this just elaborate tinkering for tinkering’s sake? That sparked the classic maker-world tension between practicality and pure curiosity. On one side: people who see a fun experiment and a love letter to old hardware. On the other: the brutally honest “what problem does it solve?” brigade.
There’s also a delicious retro-tech irony here. Kevin is digging into whether the ancient Z80 can be slowed down to a crawl — even hand-cranked levels — while readers are basically squinting at the whole thing like it’s a science fair volcano made from silicon. The unspoken meme energy is strong: modern gadget babysits grandpa chip. Even with just one skeptical comment, the mood is already wonderfully familiar — admiration, confusion, and just enough side-eye to keep the drama alive.
Key Points
- •The article documents an experiment to use an RP2350-based board to observe a Z80 processor’s address and data buses.
- •The hardware setup uses a Pimoroni PGA2350 mounted on a custom breakout PCB.
- •The post identifies key Z80 bus characteristics, including a 16-bit address bus, 8-bit data bus, and control lines such as reset and clock.
- •It reviews Z80 speed variants from early 2.5 MHz parts through later CMOS versions commonly rated at 8 MHz, 10 MHz, and up to 20 MHz, and notes the Z80 was discontinued in 2024.
- •Using Z80A timing information, the author estimates a minimum practical clock frequency of just under 5 kHz, with the recommendation that the clock be held HIGH when not cycling.