Users Manual

ALL
EFFECTIVITY
© Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 5-55
22 Apr 2019
23-15-49
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ASPIRE-400
(d) If the ACD cannot deliver an enveloped message to the destination (ACARS MU/
CMU or GDGW), the message is discarded.
NOTE: There is no support by the SDU for Williamsburg protocol command/
control messages on the CMU interface.
(3) When disabled for ATN/OSI service, the ACD negotiates a Williamsburg Version 1 data
transfer on the CMU Interface with the following data transfer speeds:
(a) When the CMU Interface is configured for high speed, the ACD transfers data
using Williamsburg V1 with standard high speed timing with the extension T16
Timer = 600 ms
(b) When the CMU Interface is configured for low speed, the ACD transfers data
using Williamsburg V1 with standard low speed timing.
(4) The ACD transmits and receives data using Williamsburg V1 protocol with the following
protocol words asynchronously shown in Table 5-19:
Table 5-19. ACP Transmit/Recieve Codes
ACP
Transmit
ACP Recieve
RTS
CTS
NCTS
BUSY
NAK
ACK
ALO
ALR
SYN
SOT
EOT
DATA
LOOP TEST
NOTE: There are no timing requirements between words or LDUs.
(5) Williamsburg V1 protocol for CMU ACARS information transfer is supported on all ORT
activated CMU interfaces using:
(a) O
1
Duplex Operation = Half Duplex
(b) O
2
Bus Speed = aligned to the ORTset CMU rate
(c) O
3
Automatic CTS when ready = No
(d) O
4
Accept Auto CTS =No
(e) O
5
Sys priority to resolve RTS conflict = Yes - SDU
(f) O
8
Support of Solo Word = yes (TEST/LOOP)
DRAFT
3rd rvw Draft as of:
29 January, 2020