The CMPS11 is Devantech's 3rd generation tilt compensated compass. Employing a 3-axis magnetometer, a 3-axis gyro and a 3-axis accelerometer. A Kalman filter combines the gyro and accelerometer to remove the errors caused by tilting of the PCB. The CMPS11 produces a result of 0-3599 representing 0-359.9 or 0 to 255. The output of the three sensors measuring x, y and z components of the magnetic field, together with the pitch and roll are used to calculate the bearing, each of these components are also made available in their raw form. The CMPS11 module requires a power supply at 3.6 - 5V and draws typically 25mA to 35mA of current. Serial and I2C interfaces are provided.