Thommen AD20 - APPENDIX II: Failure Codes

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 70 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
6.2 APPENDIX II: Failure Codes
The test duration determines the time span in which the failure shall be detected after the test is
executed. After the failure is detected the failure must obtain for the time span of the confirmation
period before it is handled and indicated.
FC Description Failure
Class /
Criticality
Instrument
Reaction
for user
001 Program checksum invalid CRIT According to Failure Class Definition
002 Parameter checksum invalid CRIT According to Failure Class Definition
005 RAM Test failure CRIT According to Failure Class Definition
006 CPU Test failure CRIT According to Failure Class Definition
007 Watchdog error during initiated test or
critical fail occurs ten times in
sequence
(prevent from permanent restart)
CRIT According to Failure Class Definition
010 ARINC 429 Interface Hardware
Failure
CRIT According to Failure Class Definition
012 I2C bus interface failure CRIT According to Failure Class Definition
013 Configuration not valid or not
initialized
CRIT According to Failure Class Definition
014 Configuration register read back of the
I/O expander are not correct
CRIT According to Failure Class Definition
021 Power failure of +3.3V CRIT According to Failure Class Definition
022 Power failure of +5V CRIT According to Failure Class Definition
024 Power failure of +15V or +15 over
current
CRIT According to Failure Class Definition
Disable +15V supply in case of over-
current
025 Power failure of -15V or -15 over
current
CRIT According to Failure Class Definition
Disable -15V supply in case of over-
current
027 Internal A/D-C reference not present
for > 1 s
CRIT According to Failure Class Definition
028 Error in the Power backup system
detected
TOL According to Failure Class Definition
040 A/D-C Error of Static pressure sensor
detected
CRIT According to Failure Class Definition