There’s a short video to go with this article where I just walk through the board features and then briefly show the programming and demo code.
When a project comes to a close and you have time to reflect then there’s always one or two things that you’d do differently and this one’s no different. Here are a few things that I’d do differently.
The ‘boot’ selector header is too close to the SWD header. With the SWD cable connected it would be a very tight fit to get a jumper across to select the RAM boot option.
If I were to shuffle a few components around I think I could probably stretch to a push-button on the board. It’s always nice to have a button.
The VDDA selection is a bit clunky. Selecting the internal 3.3V supply as the VDDA source with a jumper is obvious enough but it’s not obvious that to use an external VDDA you have to remove the jumper and connect your external supply to pin 3 in that header block. Pin 4 is effectively redundant.
Breadboard compatibility. If I increased the board size to the 10x5cm format then I’d have enough space to make the pin headers single row and thereby plug directly into a breadboard.
Want to build this board yourself? If you can handle a 0.65mm pitch IC and a generous sprinkling of 0603 passives then you should find this a breeze to build. Head on over to my downloads page to get yourself a copy of gerbers that can be directly uploaded to Elecrow, ITead, Seeed or any other of your favourite prototyping houses.