Garmin G3X Installation Manual page 196

A.3.5.3 RS-485 Input
The GSU 73 contains one channel of RS-485 serial data communications.
Pin Connector
1 P731
2 P731
A.3.5.4 CAN Bus
This data bus conforms to the BOSCH standard for Controller Area Network 2.0-B. This bus complies
with ISO 11898. One GDU 37X should be terminated (CAN BUS TERMINATION connected to CAN
BUS LO) and the GSU should be terminated if GSU is located at the end of the bus (see Appendix D).
Pin Connector
7 P731
8 P731
29 P731
A.3.5.5 Configuration Module Interface
Pin Connector
20 P732
39 P732
59 P732
78 P732
A.3.6 Discrete I/O
A.3.6.1 Active Low Discrete Inputs
The GSU 73 has 4 configurable discrete inputs conforming to:
a) Low: 0 VDC < Vin < 3.5 VDC, OR Rin < 375 ohms (active)
b) High: 8 VDC < Vin < 36 VDC, OR Rin> 100k ohms (inactive)
Pin Connector
9 P731
10 P731
11 P731
12 P731
*Indicates Active Low
Page A-12
Revision E
Pin Name
MAGNETOMETER RS-485 IN B
MAGNETOMETER RS-485 IN A
Pin Name
CAN BUS HI
CAN BUS LO
CAN BUS TERMINATION
Pin Name
CONFIG MODULE CLOCK
CONFIG MODULE DATA
CONFIG MODULE POWER OUT
CONFIG MODULE GROUND
Pin Name
DISCRETE IN* 1
DISCRETE IN* 2
DISCRETE IN* 3
DISCRETE IN* 4
I/O
IN
IN
I/O
I/O
I/O
I/O
OUT
I/O
OUT
I/O
IN
IN
G3X Installation Manual – Pinouts
190-01115-01
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IN
IN