↧
Controlling the three LEDs on PS/2 keyboards
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...
View ArticlePS/2 support on modern USB keyboards
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...
View ArticleGotcha using CAN 2 on ARM microcontrollers (e.g., STM32F415 on 1Bitsy)
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, CAN 1,...
View Article