Ben
Well-known member
Also, what are the two squares in the schematic next to the optional 100uF cap? Is it a solder jumper? Why?
Yes, that's a solder jumper that is closed in stock teensys. You can cut it with a knife and solder it closed again if need be. If this jumper is open, you can power the Teensy from Vin from batteries or a PSU and use USB for communication at the same time without backfeeding voltage into the USB port of your computer.