Users Manual

ALL
EFFECTIVITY
© Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 5-4
22 Apr 2019
23-15-49
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ASPIRE-400
4 Watchdog restart.
NOTE: The startup cause is memorized in the Historical Logs and
used to determine further startup behavior.
5 The SDU performs a Normal-Switching-On for the following startup
causes:
6 Hardware indicated Long Power Cycle when aircraft is on-ground (>
approximately 5 seconds).
7 External Reset Discrete asserted on ground for greater than 0.5
seconds.
NOTE: Requirements for specific SDU behavior during Normal-
Switching-On can be found in subsequent requirements
where the term Normal-Switching-On has been used.
8 The SDU performs a Rapid-Switching-On for the following startup
causes:
a Hardware indicated Short Power Cycle when aircraft is on-
ground (<= approximately 5 seconds).
b Power Cycle when aircraft is in-flight.
c Software triggered BITE recovery Reset.
d Hardware indicated Watchdog Reset.
e External Reset Discrete asserted in flight for greater than 0.5
seconds.
NOTE: Requirements for specific SDU behavior during
Rapid-Switching-On can be found in subsequent
requirements where the term Rapid-Switching-On
has been used.
(6) On start-up, the ACD:
(a) Validates:
1 Strapping.
2 ACD software validation.
3 Operationally critical ACD non-volatile memory.
(b) Verifies the presence and correct functionality of the security smart card.
(c) Validates FPGA operation.
(7) On completion of power-on boot, the ACD validates startup domain segregation by
confirming each Atheros switch configuration aligns to the disable state.
(8) The ACD does not release the APP and CC from reset until each Atheros switch
configuration check successfully passes.
(9) On start-up, the ACD tests the operation of the cooling fan if the temperature exceeds 0°
C (32°F) and ensure the fan can operate if needed to provide cooling during normal SDU
operation.
(10) During "Normal Switching-On", the ACD POST and Commanded Self-Test enable the
Maintenance RS-232 serial port with the following characteristics:
(a) The baud rate is 115200 baud.
DRAFT
3rd rvw Draft as of:
29 January, 2020