G900X/G950 Installation and Maintenance Manual – Pinouts
Page A-63
190-00719-00
Revision D
A.5.7
ADC ARINC 429 System ID Connections
Pin Name
Connector
Pin
I/O
ADC SYSTEM ID PROGRAM* 1
P741
6
In
ADC SYSTEM ID PROGRAM* 2
P741
71 In
The GDC 74(X) has an associated Source/Destination Identifier (SDI or System ID) that is coded into its
ARINC 429 output messages/labels. The System ID may be used to uniquely distinguish the source of
the GDC 74(X) ARINC 429 labels in a system with more than one GDC 74(X). The GDC 74(X) System
ID can be set to All Call, #1, #2, or #3 for such purposes.
By hard strapping the program pins to ground or open, the GDC 74(X) ADC (Air Data Computer) is
assigned a System ID. The System ID is included in each transmitted ARINC 429 word. The System ID
indicates that there is only a single ADC installed (All Call) or, if multiple units are installed, which ADC
the data originates from (#1, #2 or #3). When a single GDC 74(X) is installed in the system, then the
pins are left open (All Call). Table A-2 shows strapping connections to achieve the desired system ID.
Table A-2. P741 Strapping to Achieve Desired System ID
System ID Number
ARINC System ID 1
Pin 6
ARINC System ID 2
Pin 71
All Call
Open
Open
#1 Ground
Open
#2 Open
Ground
#3 Ground
Ground