Garmin G3X Installation Manual page 239

15.4.3 Serial Data
The RS-232 outputs conform to EIA Standard RS-232C with an output voltage swing of at least ±5 V
when driving a standard RS-232 load.
RS-232 channel 1 should be connected to an available RS-232 port on a GDU 37X display. RS-232
channel 2 should be connected to the GSA 28 roll servo RS-232 port in a Garmin autopilot system (see
Figure C-1.5).
Pin Name
RS-232 OUT 1
RS-232 IN 1
RS-232 OUT 2
RS-232 IN 2
SIGNAL GROUND
SIGNAL GROUND
15.4.4 Lighting
The GMC 305 can track a 14 VDC lighting bus using these inputs. The GMC 305 can also automatically
adjust for ambient lighting conditions based on photocell input. If no (0 VDC) voltage is supplied to the
lighting bus input (and unit is configured for 14 V supply), the GMC 305 will automatically adjust for
ambient lighting conditions using its built-in photocell.
Pin Name
LIGHTING BUS HI
LIGHTING BUS LO*
190-01115-01
Rev. L
Connector
J3051
J3051
J3051
J3051
J3051
J3051
Connector
J3051
J3051
G3X Installation Manual - LRU Pinouts
Pin I/O
1 Out
2 In
3 Out
4 In
6 --
8 --
Pin I/O
11 In
12 In
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