User Guide

190-00442-00 Rev. AGarmin G1000 System Overview for Mooney M20M & M20R
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SYSTEM OVERVIEW
• GIA 63 – The GIA 63 is the central ‘Integrated
Avionics Unit’ of the G1000 system. The GIA 63
functions as a main communications hub, linking all
LRUs with the PFD and MFD displays. Each GIA 63
contains a GPS receiver, VHF COM/NAV/GS receiv-
ers, and system integration microprocessors. Each
GIA 63 is paired with a respective GDU 1040 display
through Ethernet. GIAs are not paired together and
do not communicate with each other directly.
• GRS 77 – The GRS 77 is an Attitude and Heading
Reference System (AHRS) that provides aircraft atti-
tude and heading information to the G1000 displays
and the GIA 63s. The unit contains advanced sen-
sors, accelerometers, and rate sensors. In addition,
the GRS 77 interfaces with both the GDC 74A Air
Data Computer and the GMU 44 Magnetometer.
The GRS 77 also utilizes GPS signals sent from
the GIA 63. Attitude and heading information are
sent using an ARINC 429 digital interface to both
GDU 1040s and GIA 63s.
• GMU 44 – The GMU 44 Magnetometer measures
local magnetic field information. Data is sent to
the GRS 77 ARHS for processing to determine air-
craft magnetic heading. This unit receives power
directly from the GRS 77 and communicates with
the GRS 77 using RS-485 digital interface.
• GDC 74A – The GDC 74A Air Data Computer
processes information from the pitot/static system
and the outside air temperature (OAT) sensor. The
GDC 74A provides pressure altitude, airspeed,
vertical speed, and OAT information to the G1000
system. The GDC 74A communicates with both
GIA 63s, GDU 1040s, and GRS 77 using ARINC 429
digital interface.