SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
MCS--4200/7200 Multi--Channel SATCOM System
23--20--35
15 Jul 2006
Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 5--60
(5) Once a valid ICAO address is received on any bus, the SDU ignores further data
received on any of the buses until the next POST/PAST. This requirement relieves
the SDU of having to deal with the possibility that the ICAO technical address might
change while the SDU is logged-on. The AES ID (ICAO address) is determined at
startup and cannot change until the next POST/PAST. The SDU does not log-on until
it has a valid AES ID. The SDU waits indefinitely to receive a valid address from an
available ARINC 429 source rather than giving up at the end of POST/PAST, since it
cannot proceed as an AES without the address. If the configuration pin indicates the
ARINC 429 source is available, the discretes are not wired. The SDU will not revert to
the discretes at the end of POST/PAST as the CMU may not yet be operational.
(6) If configuration pin TP10A is wired to the one state, then neither CMU input port nor
the AES ID input port is capable of supplying the AES ID in the ARINC 429 format
and the SDU reads the AES ID from the discrete inputs.
(7) With either the ARINC 429 or discrete inputs source, an AES ID of all zeros or all
ones (binary) is invalid (typically indicative of an unprogrammed address) which
constitutes a failure. The SDU does not attempt to log-on to a GES with an invalid
AES ID.
C.
FMC Connection to SDU
(1) The interpretation of this configuration pin is given in Table 5-9.
Table 5-9.
FMC Connection to SDU
TP10 Pins
B
C
Interpretation
0
0
FMC NO. 1 CONNECTED, FMC NO. 2 CONNECTED
0
1
FMC NO. 1 CONNECTED, FMC NO. 2 NOT CONNECTED
1
0
FMC NO. 1 NOT CONNECTED, FMC NO. 2 CONNECTED
1
1
NEITHER FMC CONNECTED
NOTE: SATCOM does not support the FMC interface.
D.
ARINC 429 Speed to/from CMU No. 1 and CMU No. 2
(1) The interpretation of this configuration pin is given in Table 5-10.
Table 5-10.
ARINC 429 Speed to/from CMU No. 1 and CMU No. 2
TP10 Pin D
Interpretation
1
LOW SPEED ARINC 429 DATA BUS
0
HIGH SPEED ARINC 429 DATA BUS
