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Main Menu
Diagnostics
Lead/Reserve CPU Diagnostics
58
900 Control Station User Guide
Revision 9
May 2014
Class
Status
Possible Cause
Controller Action
Fix
CPU POSITION CPU-A
N/A
Normal operation
CPU-B
N/A
Normal operation
g)
CPU IS MISSING Reserve CPU is not
installed or not powered.
CPU rack backplane
failure
The lead controller
will continue to
control the process,
but failover is not
possible.
Install reserve CPU
Apply power to reserve CPU
Replace CPU rack backplane
Call Honeywell service
CPU
GOOD
N/A
N/A
N/A
ADDRESS
ERROR
The reserved exception
occurred for an unknown
reason.
See PREFETCH
ERROR.
See PREFETCH ERROR.
PREFETCH
ERROR
CPU failed when
attempting to fetch an
instruction from the
prefetch register.
1. Controller
performs a restart
2. Associated rack
monitor block’s
RACK OK pin is
turned off.
3. SYSTEM
MONITOR
block’s HW OK
pin is turned off.
1. Force a cold start.
2. Isolate system from noise and
force a cold start.
3. Replace CPU board.
DATA ABORT
ERROR
CPU failed when
attempting to access
data.
See PREFETCH
ERROR.
See PREFETCH ERROR.
S/W
INTERRUPT
ERR
Software Interrupt that is
not supported by the
software occurred.
See PREFETCH
ERROR.
See PREFETCH ERROR.
UNDEFINED
INSTR ERROR
Bad Instruction Detected
See PREFETCH
ERROR
See PREFETCH ERROR.
WATCHDOG
ERROR
Watchdog reset resulting
from software failure
1. Associated rack
monitor block’s
RACK OK pin is
turned off.
2. SYSTEM
MONITOR
block’s HW OK
pin is turned off.
1. Force a cold start.
2. Upgrade controller module
software.
3. Replace CPU board.
4. Contact Honeywell Personnel.
VECTOR
ERROR
Corrupted interrupt
vectors in RAM.
Interrupt vectors
were restored.
See WATCHDOG ERROR.
MEMORY
GOOD
N/A
N/A
N/A
5 DAY BATTERY
WARNING
Estimated battery life is
less than 5 days.
1. Associated rack
monitor block’s
RACK OK pin is
turned off.
2. SYSTEM
MONITOR
block’s HW OK
pin is turned off.
Replace battery.