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11ć6, 2 label instruction – Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual User Manual

Page 207

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Jump Instructions and

Subroutine Programming

Chapter 11

11Ć6

Figure 11.5

Multiple JUMPS to LABEL in Subroutine Area and Multiple Return Paths

to Main Program

Main Program

( JSR )

03

|ą|

| / |

|ą|

( JSR )

03

|ą|

|ą|

|ą|

( JSR )

03

|ą|

|ą|

(ą)

|ą|

(ą)

|ą|

(ą)

|ą|

LBL

(ą)

03

( RET )

(Subroutine)

Subroutine Area

A

B

C

a

b

c

The Label instruction shown in Figure 11.6 is the target destination for
both the Jump and Jump to Subroutine instructions. Labels are assigned
octal identification numbers from 00-77. The label identification number
must be the same as that of the Jump and/or Jump to Subroutine instruction
with which it is used. A label instruction can be defined only once,
meaning that a label with a given identification number can appear in only
one location. However, a Label instruction can be the target of jumps from
more than one location.

Figure 11.6

LABEL Format

LBL

(ą)

XX

XX = Octal Identification Number

|ą|

11.2
Label Instruction