Users Manual

ALL
EFFECTIVITY
© Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 5-56
22 Apr 2019
23-15-49
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ASPIRE-400
(g) O
10
Destination Code in RTS/CTS/NCTS/BUSY used = Yes
(h) O
11
Bit protocol verification = Yes
(i) O
12
Use Subsystem SAL from ALO word = No
NOTES:
1 O
6
, O
7
, O
9
are reserved
2 Both high and low speeds are required but the transmit and receive bus
speeds are always aligned, thus only Symmetric CMU timing is
supported.
3 Destination codes of M for destination of CMU, and S for destination of
SDU are per A741P2 4.7.4.1.
(6) When enabled for ATN/OSI service, the ACD negotiates a Williamsburg Version 3 data
transfer on the CMU Interface and transmits data to the active CMU with the following
protocol words asynchronously:
(a) Command Frame SOF
(b) DATA
(c) Command Frame EOF
(d) TEST.
NOTES:
1 There are no timing requirements between words or FDUs.
2 If the CMU refuses Williamsburg Version 3 during negotiation, the ACD
disables ATN services when enabled for ATN/OSI service.
(7) When enabled for ATN/OSI service, the ACD:
(a) Transfers data using Williamsburg V3 with high speed timing
(b) Transfers FDUs with payload up to 1024 bytes in length
(c) Adds a single byte header to the payload of all Williamsburg Version 3 FDUs as
follows:
1 3 MSBs = 101b (Protocol ID)
2 5 LSBs = 00000b (Protocol version).
(d) Silently discards the single byte payload header of incoming Williamsburg
Version 3 FDUs
(e) Transfers ATN data using a GFI value of 0101b.
(f) Implements Williamsburg V3 protocol (BOP) for the transfer of ACARS and/or
ATN data between the ground and ACARS/ATN CMUs, using:
1 O
1
Duplex Operation = Full Duplex
2 O
2
Bus Speed for busses = high speed
3 O
3
Automatic CTS when ready = No
4 O
8
Support of Solo Word = yes
5 O
11
Bit protocol verification = Yes
6 O
12
Use Subsystem SAL from ALO word = No
DRAFT
3rd rvw Draft as of:
29 January, 2020