Hold MENU, and select Settings > Sensors & Accessories > Compass.

Calibrate

Allows you to manually calibrate the compass sensor (Calibrating the Compass Manually).

Display

Sets the directional heading on the compass to letters, degrees, or milli-radians.

North Ref.

Sets the north reference of the compass (Setting the North Reference).

Mode

Sets the compass to use electronic-sensor data only (On), a combination of GPS and electronic-sensor data when moving (Auto), or GPS data only (Off).