The multi-task system
Operating Manual ProNumeric XCI 600 Version 07/16
69
9.3.5
System tasks
System tasks and system programs (SPGs) are started automatically by the
operating system when an event occurs in connection with the operating
system. The SPGs which can be used are listed in the following table:
No.
Name
Event
Actions
SPG 0
WARM_START
Is executed during a warm start
Retentive data is not initialised
Non-buffered data is initialized
The open function of the I/O driver is
executed
User tasks are activated
PLC switches to run status
SPG 1
COLD_START
Is executed during a cold start
All data is initialised
The open function of the I/O driver is
executed
User tasks are activated
PLC switches to run status
SPG 2
TO_STOP
Is executed when program execution
is stopped
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP
SPG 10
WATCHDOG
Is executed when a task has not been
completed within its watchdog time
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP
SPG 11
ZERODIV
Is executed if division by zero occurs
during program execution
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP
SPG 12
STACKOVER
Is executed if a stack overflow has
occurred. Is only executed if the
“Stack-Prüfung” [“Stack check”]
checkbox in the “Ressource ...
einrichten” [Resource ... Set up] dialog
in MULTIPROG was activated.
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP
SPG 13
BADCAL
Is executed if a non-existent
manufacturer-specific POU is called
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP
SPG 14
IOERROR
Is executed if an error occurs in the
I/O driver while the process is running
PLC continues execution
SPG 16
MATHERR
Is executed if a sliding point error
occurs in an arithmetic function
User tasks are deactivated
All outputs are updated
The close function of the I/O driver is
executed
PLC switches to STOP