Clough42 Explains the Raspberry Pi Pico-Based Electronics Driving His Upcoming Mechanical Clock

I think those of us with voices in the maker community tend to forget that the things we say are mostly gibberish to the vast majority of people. That can make everything we do seem inaccessible to less experienced folks. But James Clough, AKA Clough42, excels at providing explanations that anyone can grasp. His newest video — an overview of the Raspberry Pi Pico-based electronics that will drive a mechanical clock — is the perfect example.

Clough’s YouTube channel leans towards machining, 3D printing, and general fabrication, so he has the ideal audience for a video like this. You may be part of that group if you have an interest in making things, but have been overwhelmed by electronic components like microcontrollers.

Clough will ultimately make a mechanical clock and it is sure to have some extravagant mechanisms. But those will be driven by stepper motors and this video goes into detail on that. The entire purpose of the electronic “backend” is to enable extremely accurate timekeeping via GPS. All of the components that Clough selected are there to capture that time and adjust the mechanical clock accordingly.

GPS is perfect for that job, because it works through triangulation and that relies on extremely precise timing. If you can get a signal from even one GPS satellite — which should be possible anywhere on the surface of the Earth — you have a free source of accurate and precise timekeeping.

The Raspberry Pi Pico is a microcontroller development board (MDB) that grabs that time from an inexpensive GPS receiver via a UART serial connection. A small TFT LCD screen connects to the Pico through SPI and displays information on GPS signal integrity and the set time zone. Finally, the Pico controls six stepper motors through TMC2208 stepper drivers. It does that by generating the pulses that tell the stepper motors how many steps to move.

Clough provides detailed explanations about how each of those steps works.

For the demonstration, Clough built a “test fixture” to display the time. That is simple, with the stepper motors turning wheels with printed numbers in front of windows. That’s pretty cool, but I expect the actual mechanical clock design to be more extravagant and impressive, so keep an eye out for that.