Siemens SINUMERIK 828D Programming Manual page 27

Example 2: Program-global and program-local user variables (PUD/LUD)
Program code
PROC MAIN
DEF INT VAR1
...
SUB2
...
M30
Program code
PROC SUB2
DEF INT VAR2
...
IF (VAR1==1)
VAR1=VAR1+1
VAR2=1
ENDIF
SUB3
...
M17
Program code
PROC SUB3
...
IF (VAR1==1)
VAR1=VAR1+1
VAR2=1
ENDIF
...
M17
Job planning
Programming Manual, 07/2010, 6FC5398-2BP40-0BA0
Flexible NC programming
Comment
; Main program
; PUD definition
; Subprogram call
Comment
; Subprogram SUB2
; LUD DEFINITION
; Read PUD
; Read and write PUD
; Write LUD
; Subprogram call
Comment
; Subprogram SUB3
; Read PUD
; Read and write PUD
; Error: LUD from SUB2 not known
1.1 Variables
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