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7-3SectionSelf-diagnostic Functions
115
d) Use a Programming Device to set the CPM2B to PROGRAM mode.
2. I/O Wiring Checks
a) With the CPM2B in PROGRAM mode, check the output wiring by turning
on the output bits with the force set and force reset operations.
b) Check the input wiring with the CPM2B’s input indicators or a Program-
ming Device’s monitor operations.
3. Test Run
a) Use a Programming Device to set the CPM2B to RUN or MONITOR
mode and check that the “RUN” indicator lights.
b) Check the sequence of operation with the force set/reset operations, etc.
4. Debugging
Correct any programming errors that are detected.
5. Saving the Program
a) Use a Programming Device to write the program to a backup floppy disk.
b) Print out a hard copy of the program with a printer.
Note Refer to Section 4 Using Programming Devices for details on the Support Soft-
ware and Programming Console operations.
7-3 Self-diagnostic Functions
The CPM2B is equipped with a variety of self-diagnostic functions to help iden-
tify and correct errors and reduce down time.

7-3-1 Identifying Errors

An error can be identified by the error message displayed on a Programming
Device, error flags in the AR and SR areas, and the error code output to SR 253.
PC errors are divided into 2 categories based on the severity of the errors. The
status of the ERR indicator (lit or flashing) shows which type of error has oc-
curred.
ERR Lit (Fatal Error)
Fatal errors are serious errors which stop CPM2B operation. There are two ways
to restart operation:
•Turn the PC off and then on again.
•Use a Programming Device to switch the PC to PROGRAM mode, and read/
clear the error.
ERR Flashing (Non-fatal Error)
Non-fatal errors are less serious errors which don’t stop CPM2B operation.
When an error is detected, a corresponding error message will be displayed on
the Programming Console or other Programming Device connected to the PC.
When a hardware error is detected, the corresponding error flag in the AR or SR
area will be turned ON.
When an error is detected, a specific 2-digit hexadecimal error code is output to
SR 25300 to SR 25307. The error code and time of occurrence are also output to
the Error Log Area (DM 2000 to DM 2021).
WARNING When the CPM2B’s self-diagnosis function detects a fatal error or when a
severe failure alarm (FALS) instruction is executed, PC operation will stop and
all outputs will be turned OFF. External safety measures must be provided to
ensure safety in the system. Not providing proper safety measures may result in
serious accidents.
Fatal and Non-fatal
Errors
Error Messages
Error Flags
Error Code