This might be a silly question, but I have a switch in my car that I’d like to read, and it pulls to earth when closed.
I have both my Arduino, and another controller that need to read this switch position, and the other controller can use a 10k input pullup. Can I do the same thing on the same wire with the Arduino without causing either device any upset? I guess yes…? Do I need any circuit protection in this case or simply wire both to the switch?