Siemens SINUMERIK 840Di Function Manual page 613

Example:
The synchronous spindle coupling at the beginning of the SERUPRO operation is retained
for the part program start.
$MC_START_MODE_MASK = 'H400'
$MC_START_MODE_MASK_PRT = 'H00'
$MC_ENABLE_START_MODE_MASK_PRT = 'H01'
2.6.9 System variables and variables for SERUPRO sequence
SERUPRO detection
The SERUPRO sequence can be detected using the following system variables:
$P_ISTEST is TRUE (valid also for program test)
$P_SEARCH is set to 5 (search in extended program test)
$AC_ASUP Bit 20 in system ASUB is set after the search target
is found (SERUPRO operation step 8.)
$P_ISTEST AND (5 == $P_SEARCHL) reliably detects SERUPRO.
$AC_SEARCH is not supplied by the SERUPRO operation.
Note
$P_SEARCHL is set at the beginning of the SERUPRO operation and
reset on RESET. As a result, $P_SEARCHL continues to be set in the SERUPRO ASUB and
in the residual part program and can continue to be evaluated.
In contrast, the $P_ISTEST variable is set only in the SERUPRO operation and is thus
suitable for searchspecific adaptation of programs.
Mode Group, Channel, Program Operation, Reset Response (K1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
2.6 Block search Type 5 SERUPRO
; Synchronous spindle coupling not
configured
; Is switched off
; Remains active
; $MC_START_MODE_MASK_PRT is evaluated
in SERUPRO instead of
$MC_START_MODE_MASK
Detailed Description
2-77