User's Guide

Table Of Contents

DRAFT

Page 3-2

17 Mar 2016

23-15-87

SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL

ARINC 781-500 SDU and SCM

1. Install the SDU in a 6 MCU tray as per ARINC 600. The minimum clearance between the SDU and

any other equipment installed above it shall be no less than 0.5 inches (12.7 mm).

2. Install the SCM in any orientation. Refer to Table 1-2 on page 5 for the SCM mounting specification.

• There are no clearance requirements for the SCM.

3. Connect the SCM to the SDU. The SDU supports one RS-422 interface for interconnect to the SCM.

4. Connect the SDU to the antenna subsystem. The SDU supports ARINC 429 communication to and

from the antenna subsystem.

5. Connect the SDU to the TCP(s). The SDU supports three ARINC 429 receive interfaces and one

ARINC 429 transmit interface for interconnect to the flight deck TCP(s).

4. Connection Details

A. SDU

The SDU uses two external interface connectors:

• Rear Connector—a low insertion force, size 2 shell receptacle accommodating coaxial and sig-

nal interconnections in the top plug insert, Quadrax and signal connections in the middle plug

insert, and coaxial and power interconnections in the bottom plug insert. Pin assignments are

compliant with ARINC Characteristic 781 with top plug and middle plug deviations as shown in

Table 3 - 1 .

• Front Connector—an RJ45 and 9S DSUB connector providing 10BaseT Ethernet interfaces

and an RS-232 maintenance interface. Pin assignments are shown in Table 3-2. The front

connector is behind a maintenance cover. This connector provides access to maintenance and

troubleshooting information when the SDU is not in normal operation.

Table 3-1. SDU Rear Connector Pin Deviations

Pin Number A781 Deviation

TP01C ATE pin 3 Data I/O Processor Maintenance GND

TP01D ATE pin 4 Data I/O Processor Maintenance TXD

TP01E ATE pin 5 Data I/O Processor Maintenance RXD

TP01F ATE pin 6 CC1 Processors #1 & #2 Maintenance GND

TP01G ATE pin 7 CC1 Processor #1 Maintenance TXD

TP01H ATE pin 8 CC1 Processor #1 Maintenance RXD

TP01J ATE pin 9 CC1 Processor #2 Maintenance TXD

TP01K ATE pin 10 CC1 Processor #2 Maintenance RXD

TP02A ATE pin 11 Shopload

TP02C ATE pin 13 Voice Processor Maintenance GND

TP02D ATE pin 14 Voice Processor Maintenance TXD

TP02E ATE pin 15 Voice Processor Maintenance RXD

TP02F ATE pin 16 CC2 Processor Maintenance GND

DRAFT as of

4 Mar 2016