Moog Crossbow NAV440 Series - Manual (Page 93)

NAV440 User Manual
7430‐0131‐01 Rev. F
Page 93
Chapter 11. Built In Test(BIT)
The Built‐In Test capability allows users to monitor health, diagnostic, and system status information of the unit in
real‐tim
on e. Built‐In Test informati is transmitted in each measurement packet.
NOTE: A diagnostic test packet (T0) can be requested via GP. To contains a complete set of status for each hardware
and software subsystem. For more information, refer to Chapter 10. Programming Guidelines, Test 0 (Detailed
BIT and Status) Packet on page 71 and Get Packet Request on page 66.
BIT Status Fields
Error A BIT word consists of two bytes: byte and Status byte.
The first byte (bits 0–7) is the Errorbyte: signaled results from internal checks. Four intermediate signals determine
when to assert masterFail and the hardware BIT signal. These signals are controlled by three categories of systems
checks: hardware (hardwareError), communication (comError) and software (softwareError). Instantaneous soft
failures from any category triggers the signals: a flag is raised. masterFail is not triggered until persistency
e has occu conditions are met or a hard failur rred.
The second byte (bits 8–15) is the Statusbyte: signaled status alerts. Four intermediate signals determine when to
assert the masterStatus flag: hardwareStatus, sensorStatus, comStatus, and softwareStatus. masterStatus is the
logical OR of these intermediate signals. Each intermediate signal has a separate field with an indication flag. Each
indication flag can be enabled or disabled by the user. Any enabled indication flag will trigger the associated
tus intermediate signal and masterSta
The BIT fields are summarized in Table 81
flag.
below. provides additional information about the programmable
status field.
Table 82
Table 81 Default BIT Status Values
BITstatus Field Bits Value Config able ur
Error Byte fields (BIT) N
masterFail 0 0: no
1: fatal error
The masterFail rmal
flag is thrown when either a hard failure (fatal
or a soft failure (persistent problem) occurs. condition)
N
hardwareError 1 0: normal
hardware error 1: internal
N
comError 2 0: normal
ication error 1: commun
N
softwareError 3 0: normal
ernal software error 1: int
N
Reserved 4:7 N/A N
Status Byte Fields
masterStatus 8 0: nominal
1: one or more status alerts occurred: hardware; com; software;
sensor
Y