User's Manual

Table Of Contents
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ARINC 781-200 SDU and SCM
23-15-30 2-16
DATE TBD
You can view the following information from this screen:
SDU status on the line below SDU
Overall health of all subsystem components (SCM, DLNA, and HGA) on the line
below SUBSY HLTH
Thermal status of the SDU and HGA on the line below OVERTEMP
SCM health on the line below SCM
Peripheral LRU bus status on the line below SYS BUS
Subsystem bus status on the line below S
UBSY BUS
The number of functioning SBB channels and Classic channels below CH-SB
B
CLSC
RF path status on the line below RF PA
TH
USIM and data bus status on the line below US
IM/DATA
NOTE: Valid values for status are OK and FAIL. If the status of a subsystem is
FAIL, press the button next to the subsystem to view the details.
To view more information about the health of a pa
rticular subsystem, press the button
next to the name of the subsystem. For more information about the various MCDU menu
screens, see "Troubleshooting and Fault Isolation" on page 4-7.
3. Channel Status and System Configuration
A. SBB Status
Depending on the SCM installed with the SDU, the A781-200 system can support single
SBB or dual SBB.
In single SBB
mode, the SDU supports
up to 2 simultaneous voice calls (one on classic
and one on SBB) on the CEPT-E1 interface. In this mode, the SBB menu has one page.
In dual SBB mode, the SDU supports up to 3 simultaneous voice calls (one
on classic
and two on SBB) on the CEPT-E1 interface. In this mode, the SBB menu has two pages.