Siemens SINUMERIK 840D sl Programming Manual page 551

Example
Nesting of untraceable program sections in two program levels with implicit IPTRUNLOCK.
Implicit IPTRUNLOCK in subprogram 1 ends the untraceable section.
Program code
N10010 IPTRLOCK()
N10020 R1 = R1 + 1
N10030 G4 F1
...
N10040 subprogram2
...
N20010 IPTRLOCK ()
...
N20020 IPTRUNLOCK ()
N20030 RET
...
N10060 R2 = R2 + 2
N10070 RET
N100 G4 F2
The interruption pointer then produces an interruption at 100 again.
Acquiring and finding untraceable sections
Non-searchable program sections are identified with language commands IPTRLOCK and
IPTRUNLOCK .
Command IPTRLOCK freezes the interruption pointer at a single block executable in the
main run (SBL1). This block will be referred to as the hold block below. If the program is
aborted after IPTRLOCK, this hold block can be searched for from the HMI user interface.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
8.5 Preventing program position for SERUPRO (IPTRLOCK, IPTRUNLOCK)
Comment
; Hold block of the search-suppressed program
section starts.
; Interpretation of subprogram 2
; Ineffective, repeated start.
; Ineffective, end at another level.
; End of search-suppressed program section.
; Main program is continued.
Path traversing behavior
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