Genesys GDR- COM Series, Installation Manual, Page: 37 / 62

GDR-XXXX NAV/COM INSTALLATION MANUAL
CHAPTER 2 – SYSTEM INSTALLATION
64-000109 Page 37 of 62
H. SDI, Power, and Discrete
Two pins on the P2 connector are used to set the ARINC 429 Source/Destination
Identifier (SDI), one pin is used to remotely turn on the radio, and one pin to tune to
the Emergency frequency.
An open condition is valid when the input is above 12VDC. A ground condition is
valid when the input is below 2VDC.
The two SDI pins are used to identify the identification of the radio for the ARINC
429 words. The combination of SDI1 and SDI2 will determine NAV/COM1 through
NAV/COM3 as noted below.
SDI1 SDI2 NAV/COM
OPEN OPEN “All Call”
OPEN GND 1
GND OPEN 2
GND GND 3
The PS ENABLE pin enables the power supply of the radio on when grounded.
This pin may be wired to a control head power switch or permanently wired to
ground. When permanently wired to ground, the unit will activate when 28 Volt
power is applied.
The EMERGENCY pin will tune the VHF and UHF transceivers to the emergency
frequency of 121.5MHz (VHF) and 243.00MHz (UHF) when grounded.
Conn Pin Description
P2 7 SDI1
P2 8 SDI2
P2 35 PS ENABLE
P2 36 EMERGENCY