User guide

Chapter 15
Instruction Set Overview
15–8
Control Instructions – Chapter 25
Instruction Name
and Mnemonic
5/02
Only
•
Function – Conditional Input or Output
Instructions
as Noted
Jump to Label JMP Output instruction. When rung conditions are true,
the JMP instruction causes the program scan to
jump forward or backward to the corresponding
LBL instruction.
Label LBL Conditional instruction. This is the target of the
correspondingly numbered JMP instruction.
Jump to Subroutine JSR Output instruction. When rung conditions are true,
the JSR instruction causes the processor to jump
to the targeted subroutine file.
Subroutine SBR Conditional instruction. Placed as the first
instruction in a subroutine file. Identifies the
subroutine as a non–interrupt file.
Return from Subroutine RET Output instruction, placed in subroutine. When
rung conditions are true, the RET instruction
causes the processor to resume program
execution in the main program file or the previous
subroutine file.
Master Control Reset MCR Output instruction. Used in pairs to inhibit/enable a
zone within a ladder program.
Temporary End TND Output instruction. When rung conditions are true,
the TND instruction stops the program scan,
updates I/O and communications, then resumes
scanning at rung 0 of the main program file.
Suspend SUS Output instruction, used for troubleshooting. When
rung conditions are true, the SUS instruction
places the controller in the Suspend Idle mode.
The suspend ID number is placed in word S:7 and
the program file number is placed in S:8.
Selectable Timed Disable
Selectable Timed Enable
Selectable Timed Start
STD
STE
STS
•
•
•
Output instructions, associated with the Selectable
Timed Interrupt (STI) function. STD and STE are
used to prevent an STI from occurring during a
portion of the program; STS initiates an STI.
Interrupt Subroutine INT
•
Conditional instruction. Placed as the first
instruction in a Selectable Timed Interrupt
subroutine file or an I/O Event–Driven Interrupt
subroutine file. Identifies the subroutine as an
interrupt file.