appunti di Ermanno Goletto
External 6V battery (+) ───────> VM External 6V battery (-) ───────> GND
// Motor 2 reverse at 50% speed digitalWrite(in3, LOW); analogWrite(in4, 127); hw-417-v1.2 driver
void setup() pinMode(in1, OUTPUT); pinMode(in2, OUTPUT); pinMode(in3, OUTPUT); pinMode(in4, OUTPUT); External 6V battery (+) ───────>