The short version: The CAN bus 2 channel on ARM microcontrollers only works if CAN 1 is also set up… That is, CAN 2 can not be set up independently; for it to work at all, the other CAN channel, …
Gotcha using CAN 2 on ARM microcontrollers (e.g., STM32F415 on 1Bitsy) Read more »
The short version: Two external pull-up resistors of 10 kΩ on the PS/2 DATA and CLK signal lines (corresponding to USB signal lines D- and D+, respectively) are sufficient to interface to a PS/2-capable USB keyboard. Say, to get a macro …
When repurposing old (or new) PS/2 keyboards as macro keyboards (because they are much easier to interface with than USB keyboards), there are three free LEDs that can also be repurposed, e.g., for various status purposes (say, indicating a macro …