Raspberry Pi Pico PCB uses all 26 pins in custom capacitive touch sensor

The Raspberry Pi Pico is a very handy microcontroller with plenty of GPIO pins to tinker with. Each of these pins is designated to a particular protocol but none of that matters to maker and developer Tom Fox. In his latest project, Fox demonstrates another useful yet somewhat primitive feature of these pins. Fox has created a custom PCB he calls Spoke that turns all 26 pins on the Pico into an individual touch sensor.

YouTube

Watch On

According to Fox, the idea began when he first realized that he could use a 1M resistor to transform one of the GPIO pins on the Pico into a touch-sensitive input sensor. Understanding resistor values can be tricky, our Decoding Resistors reference guide is handy to keep around when working on projects like these. From there, he took the idea and ran with it, going so far as to create a custom PCB to better prototype with the idea.

We're no strangers to creating a touch-input device on the Pico. We even put together our own guide on how to create a banana-based touch input device. However, you can do so much more with this idea than just play around with fruit and Fox demonstrates that well. He suggests it could help people create things like accessibility devices or tools for professional environments that require testing with prototype work.