#include /* Example on a 32-pin ATMega4808, LED on pin D7 */ const uint8_t unusedPins[] = {0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25}; void setup() { uint8_t index; /* Ensure unused pins are not floating */ for (index = 0; index < sizeof(unusedPins); index++) { pinMode(unusedPins[index], INPUT_PULLUP); LowPower.disablePinISC(unusedPins[index]); } /* LED is connected to D7 */ pinMode(LED_BUILTIN, OUTPUT); digitalWrite(LED_BUILTIN, LOW); LowPower.powerDown(); } void loop() { }