wire scl to analog in wire sda to analog in
void setup() {
Wire.begin(4);
Wire.onReceive(dataReceived);
}
void dataReceived(int howMany) {
while ( Wire.available() > 0 ){
int n = Wire.read();
Serial.printf('Received %d\n',n);
}
arduino = I2C{I2C.Port.kOnboard, 4};
byte b = (byte) 1;
arduino.transaction(b, b.length, null, 0);