Rockwell Automation 57C435 Processor Module, AutoMax - Manual (Page 19)

3Ć5
3.5 Processor Module Diagnostics
This section describes the Processor module powerĆup and runĆtime
diagnostics.
3.5.1 PowerĆUp Diagnostics
When you first turn on power to the Processor module or cycle
power, it will run diagnostics on the Eprom and RAM memory,
memory management unit, watchdog timer, parity, interrupts, and
SIO.
If morethan oneProcessor is located in therack, theleftmost
Processor will also run diagnostics on the Common Memory module.
While running diagnostics, which take approximately 5-15 seconds,
theProcessor modules in therack will display thecodedd". When a
module has completed its diagnostics, the LED on the faceplate
labeled OK" will be turned on.
Should a malfunction be detected, all Processors in the rack will be
shut down and thestatus codeindicating which diagnostic failed will
remain on the LED display of the Processor at fault. See Appendix D
for a list of powerĆup diagnostic error codes.
After diagnostics are complete, the Processor begins periodically
resetting its watchdog to indicate that it is functioning correctly. In a
multiple Processor configuration, all of the Processors in the rack will
begin resetting the system watchdog located on the Common
Memory module in addition to resetting their own watchdogs. The
Processor module will reset its own watchdog regardless of whether
the operating system is loaded or not.
Should any watchdog beallowed to expireat any timeafter
powerĆup diagnostics are complete, all Processors in the rack will be
shut down. If application tasks arecurrently running in therack, they
will be stopped. The green LED labeled OK" on the faceplate of the
module at fault will be turned off. This Processor will assert a signal
on the backplane to reset (set 0, FALSE, or OFF) all local and remote
I/O modules.
3.5.2 RunĆTime Diagnostics
During runĆtime, i.e., while executing application tasks, the Processor
continuously performs realĆtime checking of byte parity on the RAM.
The memory management unit (MMU) checks for errors such as
writing to locations that arereadĆonly. Should any malfunction be
detected, an error code will be displayed on the LEDs and the
Processors in the rack will be either stopped or completely shut
down, depending upon the severity of the error. See Appendix E for
a list of runĆtime error codes.
Serious hardware malfunctions, however, can result in application
tasks that are currently running being stopped, the OK" indicator
being turned off, and the Processor being shut down. Once a
Processor module has shut down, it will not execute any instructions
or respond to commands from the personal computer until it is reset
by cycling power.