SWD Featherwing
A featherwing for Adafruit feather dev boards, including some extra prototyping space. This design is based on the great tutorial available on learn.adafruit.com. The repository containing the project files and information for that project is available at mikeysklar/debug-header-feather. This project is licensed under the GPL-3.0, as a derivative work.
BOM
| Ref | Value | Link |
|---|---|---|
JST |
JST-PH 2-pin Connector | (adafruit) |
SWD |
SWD 10-pin Connector | (adafruit) |
PWR |
Power LED* | (digikey search) |
-- |
12- and 16-pin Stacking Headers ** | (adafruit) |
-- |
Break-apart Male Headers*** | (adafruit) |
* The single 0603/1608 Power indicator LED can be totally omitted if you don't want to deal with a package that small. Keep in mind that this LED should be mounted upside-down on the pads on the bottom of the board
** These should be used on the feather that you're planning to debug, not this featherwing!
*** Adafruit sells a pair of 12- 16-pin male headers specifically for feathers/wings, but these pins are a bit shorter than the normal male pins that the stacking headers are designed to pair with. It's never a bad idea to have a few more of these on hand, so buying some extras isn't too bad!
Depending on your debugging setup, you will need some additional cables/adapters/hardware. If you aren't sure what components/parts you need, the original tutorial linked above contains links to all the parts you need for the SEGGER J-Link (edu version linked here, note the license restrictions).
Power LED
The power LED here can be any random 0603-size LED from any retailer. I've linked a digikey search in the BOM that filers down to the in-stock, correct package LEDs available. Adafruit doesn't seem to have any loose LEDs in this package (understandable, it's very small). I just had a reel of these on hand, so I used what I had. It would not be difficult to replace the footprint in the KiCad project.
The idea is that this LED is installed upside-down on the bottom of the board, and shines through the area in the board that's clear of copper/soldermask. You could install it right-side-up without issue - I just wanted to try out this reverse-lit PCB design.
Where to get
This project is available on OSH Park if you don't mind a purple solder mask. 3 of these bad boys can be yours for about $9. I should note, I have not ordered any of these boards from OSH Park, so I can't attest to how well they'll turn out. I highly recommend buying the parts from Adafruit - the same parts can be had elsewhere, potentially even for a small discount, but Adafruit is a great company and I'm happy to support them.