Note: Some pins are not connected on a standard Arduino Uno R3 but still listed so you can use them if you had a custom board. It might also be possible that your ICSP header of the 16u2 is flipped ...

I/O Voltage – 5V DC Current per I/O pin – 8 mA Arduino UNO R4 WiFi only Qwiic I2C connector for expansion modules. 3-pin header with an “OFF” pin to turn off the board and a “VRTC” pin to keep the ...

Clone this wiki locally (c) pighixxx Note: Some pins are not connected on a standard Arduino Uno R3 but still listed so you can use them if you had a custom board. It might also be possible that your ...