Jump Instructions - Siemens SIMATIC S7-200 System Manual

Jump Instructions

The Jump to Label instruction (JMP) performs a branch to
the specified label N within the program.
The Label instruction (LBL) marks the location of the jump
destination N.
You can use the Jump instruction in the main program, in
subroutines, or in interrupt routines. The Jump and its
corresponding Label instruction must always be located
within the same segment of code (either the main program,
a subroutine, or an interrupt routine).
You cannot jump from the main program to a label in either
a subroutine or an interrupt routine. Likewise, you cannot
jump from a subroutine or interrupt routine to a label outside
that subroutine or interrupt routine.
You can use a Jump instruction within an SCR segment, but
the corresponding Label instruction must be located within
the same SCR segment.
Table 6-58 Valid Operands for the Jump Instructions
Inputs/Outputs Data Types
N WORD
Example: Jump to Label Instruction
Operands
Constant (0 to 255)
Network 1 //If the retentive data has not been lost,
//Jump to LBL4
LDN SM0.2
JMP 4
Network 2
LBL 4
S7-200 Instruction Set Chapter 6
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