Table 5-8 Gtx 3X5/3X5R Encoded Altitude Pin Assignments; Altitude Functions - Garmin GTX 330D Maintenance Manual

5.4.3

Altitude Functions

Gillham code altitude inputs are considered active if either the voltage to ground is < 1.9 V or the
resistance to ground is < 375 . These inputs are considered inactive if the voltage to ground is
11-33 VDC. The GTX 3X5/3X5R discrete I/O pins are configurable. If the Gillham input is not enabled in
the configuration menu, then the Gillham code altitude pins can be used for other discrete input functions.
If the Gillham input is enabled, these pins will not be available for selection on other discrete inputs in the
configuration menu.

Table 5-8 GTX 3X5/3X5R Encoded Altitude Pin Assignments

Pin Name
ALTITUDE D4
ALTITUDE A1
ALTITUDE A2
ALTITUDE A4
ALTITUDE B1
ALTITUDE B2
ALTITUDE B4
ALTITUDE C1
ALTITUDE C2
ALTITUDE C4
ALTITUDE COMMON
190-00734-11
Rev. 6
Pin Number
13
10
32
53
11
33
54
12
34
55
56
GTX 33X and GTX 3X5 ADS-B Maintenance Manual
I/O Connector
In
In
In
In
In
In
In
In
In
In
--
J3251
J3251
J3251
J3251
J3251
J3251
J3251
J3251
J3251
J3251
J3251
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