Garmin G300 Pilot's Manual page 21

• GMU 44
Magnetometer: Measures the local magnetic field and sends data to the
–
AHRS for processing to determine aircraft magnetic heading. This unit
receives power directly from the AHRS and communicates with it via an
RS-485 digital interface.
• GTP 59
Temperature Probe: Provides raw air temperature data.
–
190-00921-00 Rev. D
GMU 44
GTP 59
Garmin G300 Pilot's Guide
System Overview
3