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2.5.10 Debugging and failure diagnosis instructions
Table 2.27 Debugging and Failure Diagnosis Instructions
Category
Instruction Symbol
Symbol Processing Details Execution
Condition
Number of Basic Steps
Subset
See for Description
Checks
CHKST
•The CHK instruction is executed when
CHKST is executable.
•Jumps to the step following the CHK
instruction when CHKST is in a
non-executable status. 1 - 7-175
CHK
•During normal conditions SM80 : OFF,
SD80 : 0
•During abnormal conditions SM80 : ON,
SD80 : Failure No.
CHKCIR •Starts update in ladder pattern being
checked by the CHK instruction. 1 - 7-179
CHKEND
•Ends update in ladder pattern being
checked by the CHK instruction.
CHKST
Check condition
CHK
CHKCIR
CHKEND