PRICES MAY VARY. GPIO status LED: LED on if GPIO outputs/inputs high level, LED off if GPIO outputs/inputs low level. It is a useful tool for troubleshooting and debugging I/O without the need for a meter or getting into the software. The Nano break board features a 3-pin interface with 5V and GND pins for easy connection to sensor modules or SG90 servos, along with a 5V/2A independent power supply for extra power to servos and sensors. Digital IO port 14 ports prepared to digital modules or ser