Users Manual

ALL
EFFECTIVITY
© Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 5-54
22 Apr 2019
23-15-49
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ASPIRE-400
(a) Determining active CMU receive interface
Table 5-18. Label 270 Subsystem Identifier
Bit Range Field Name (Discrete Format) Valid Values/Ranges
1-8 Label 270o
9-10 SDI 00b – Single CMU
01b – Left
10b – Right
11-15 Not Applicable
16 MU/CMU Fail MU/CMU Fail
17-19 Not Applicable
20
Active/Standby 0 – Standby
1 – Active
30-31 SSM 00b – Normal Operation
10b – Functional Test
32 Parity
Odd
(2) When configured by ORT, the ACD processes the following ARINC 429 labels, received
on the enabled CMU interfaces, "Data from CMU 1" and "Data from CMU 2", with a
period of 500 ms to 1.5 s:
(a) Label 214 and Label 216 (ICAO address, part 1 & part 2).
(3) The ACD permits Label 172o on the ORT activated CMU interfaces. No action is taken on
the content of this label. This label may or may not be present on all A429 receive
interfaces.
M. Williamsburg Protocol
(1) Williamsburg protocol is used to transfer file data to and from the CMU. During protocol
setup, the version used is negotiated on the interface (CMU, and MCDU when configured
for WSCI). For the future, it is anticipated that ACARS and ATN data will share the same
Williamsburg connection for data transfer.
(2) Once the Williamsburg version has been negotiated on the CMU interface, the following
occurs regardless of the version negotiated:
(a) The ACD transmits data to the active CMU using CMU SAL = 304o.
(b) The ACD receives data from the active CMU with the following SAL:
1 SDU #1 SAL = 307o when configuration strapped for SDU #1
2 SDU #2 SAL = 173o when configuration strapped for SDU #2
(c) The ACD transfers ACARS data using a General Format Identifier (GFI) value of
1110b.
DRAFT
3rd rvw Draft as of:
29 January, 2020