Raspberry Pi Pico 2 Logic Analyzer
This Raspberry Pi Pico 2-based logic analyzer samples up to 120 channels at 400 MHz.
A logic analyzer can be a very useful tool when working with digital electronics. They can also be rather expensive. As demonstrated in the Happy Little Diodes in the video below, with the proper code and add-on circuitry, you can also use a Raspberry Pi Pico 2 as a rather impressive logic analyzer.
This design, found on GitHub by Dr. Gusman (AKA Agustín Gimenez Bernad), has gone through several revisions, and it features both a hardware component as well as a Python-based analyzer software package for viewing results on your computer. The newest version of the board uses a soldered-on Pico 2 as its processing unit, and employs level-shifting ICs, along with connectors that allow you to daisy-chain up to five of these boards together.
One of these Pico-based boards boards can sample up to 24 channels at a time at 200 MHz, or 400 MHz in short bursts. With five boards linked together, it/they can sample a staggering 120 channels simultaneously, which seems like a ridiculously high number… until you find that niche use where you really need it. It’s always good to have options!
While Happy Little Diodes didn’t design the logic analyzer board itself, he does a great job of demonstrating how it works, using a ZX Spectrum as his analysis target. He even designs his own PCB to interface with this classic computer. This was his first foray into the world of KiCad, and PCBs in general, though if he’s anything like me it likely won't be his last!