You can watch a full video version with more details here.

New PCBs have arrived. Did they work? Hahahaha - well, mostly.

The simplest part of the PCB does not work. The LED…

What went wrong? Common cathode, vs common anode. I designed the board for common cathode, and then specced common anode for the component.

Here’s the schematic and PCB layout.

And here’s the correct schematic.

It’s not a difficult fix though - desolder the LED, and cover up the ground pad with solder resist.

And then solder the LED back on and attach a little wire to the 3V3 rail. This was a pain - and involved a lot of swearing.

A working blink sketch appears!

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