Siemens SINUMERIK 840D sl Function Manual page 639

Value Meaning
0
1
● For replacement subprograms with the attribute DISPLOF in the block display, the program
line is displayed as actual block, which resulted in the subprogram being called.
● In the replacement subprogram, areas or the complete replacement subprogram can be
protected against interruptions, such as NC stop, read-in inhibit etc., using the
DELAYFSTON and DELAYFSTOF commands.
● Replacements do not occur recursively, i.e. the function that has led to the replacement
subprogram call is no longer replaced if it is programmed again in the replacement
subprogram.
Output of auxiliary functions to PLC
When replacing auxiliary functions, calling the replacement subprogram does not initiate that
the auxiliary function is output to the PLC. The auxiliary function is only output if the auxiliary
function is reprogrammed in the replacement subprogram.
Behavior during block search
The replacement subprogram is also called in the search modes "Block search with calculation"
and "Block search with calculation in the program test mode" (SERUPRO). Any special
features must be implemented in the replacement subprogram using the system variable:
$P_SEARCH, $AC_SERUPRO.
Regarding collecting actions for "search with calculation", replacement subprograms behave
just like "normal" subprograms.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
The replacement subprogram behaves like a "normal" subprogram:
● Return jump with M17: Stop at the end of the subprogram
Note
The output of the M function at the PLC depends on:
MD20800 $MC_SPF_END_TO_VDI, bit 0 (subprogram end to PLC)
- Bit 0 = 0: No output
- Bit 0 = 1: M17 is output to the PLC.
● Return jump with RET: No stop at the end of the replacement subprogram
In the block, in which the replacement subprogram is called, only one stop is made. Regardless
of whether:
● The subprogram was called at the block start and/or at the block end
● Other subprograms are called in the subprogram
● The subprogram is exited with M17 or RET
The single-block stop takes place for the replacement of M functions at the end of the replace‐
ment subprogram.
For the replacement of T and D/DL functions, the time of the single-block stop depends on
when the subprogram is called:
● Call at block start: Single-block stop at the end of the block
● Call at the block end: Single-block stop at the end of the replacement subprogram
K1: Mode group, channel, program operation, reset response
9.17 Replacing functions by subprograms
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