simple north paw

NorthToe.ino

#include <Wire.h>
void setup()
{
  Wire.begin();
}

void loop()
{
  Wire.beginTransmission(0x21);
  Wire.write("A");
  Wire.endTransmission();
  delay(10);
  Wire.requestFrom(0x21, 2);
  unsigned int headingValue = ((Wire.read() <<8) | Wire.read());
  digitalWrite(13, headingValue < 75 || headingValue > 3525);
}