Omron CJ1G-CPU series, Programming Manual

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67
Checking Programs Section 2-3
In the rare even that this error does occur, it will be treated as a program error,
operation will stop (fatal error), and the UM Overflow Flag (A29515) will turn
ON.
2-3-4 Checking Fatal Errors
The following errors are fatal program errors and the CPU Unit will stop run-
ning if one of these occurs. When operation is stopped by a program error, the
task number where operation stopped will be stored in A294 and the program
address will be stored in A298/A299. The cause of the program error can be
determined from this information.
Note If the Error Flag or Access Error Flag turns ON, it will be treated as a program
error and it can be used to stop the CPU from running. Specify operation for
program errors in the PLC Setup.
Address Description Stored Data
A294 The type of task and the task number at the
point where operation stopped will be stored
here if operation stops due to a program error.
FFFF Hex will be stored if there are no active
cyclic tasks in a cycle, i.e., if there are no cyclic
tasks to be executed.
Cyclic task: 0000 to 001F Hex (cyclic tasks 0 to 31)
Interrupt task: 8000 to 80FF Hex (interrupt tasks 0 to 255)
A298/A299 The program address at the point where opera-
tion stopped will be stored here in binary if
operation stops due to a program error.
If the END(001) instruction is missing (A29511
will be ON), the address where END(001) was
expected will be stored.
If there is a task execution error (A29512 will be
ON), FFFFFFFF Hex will be stored in A298/
A299.
A298: Rightmost portion of program address
A299: Leftmost portion of program address
Program error Description Related flags
No END Instruction An END instruction is not present in the
program. The No END Flag (A29511) turns ON.
Error During Task Execution No task is ready in the cycle.
No program is allocated to a task.
The corresponding interrupt task num-
ber is not present even though the exe-
cution condition for the interrupt task
was met.
The Task Error Flag (29512) turns ON.
Instruction Processing Error (ER Flag
ON) and Stop Operation set for Instruc-
tion Errors in PLC Setup The wrong data values were provided
in the operand when an attempt was
made to execute an instruction. The ER Flag turns ON and the Instruc-
tion Processing Error Flag (A29508)
turns ON if Stop Operation set for
Instruction Errors in PLC Setup.
Illegal Access Error (AER Flag ON) and
Stop Operation set for Instruction
Errors in PLC Setup A read or write was executed for a
parameter area.
A write was executed in a memory area
that is not mounted (see note).
A write was executed in an EM area
specified as EM File Memory.
A write was executed in a read-only
area.
The value specified in an indirect DM/
EM address in BCD mode was not
BCD.
AER Flag turns ON and the Illegal
Access Error Flag (A29510) turns ON if
Stop Operation set for Instruction
Errors in PLC Setup