Siemens SINUMERIK 840D sl Function Manual page 559

Interrupt routines
Interrupt routines are NC programs which are started by interrupt events (interrupt inputs,
process or machine status).
A part program block currently being executed will be aborted by the activation of an interrupt
routine if it is not specifically declared to be locked against interruption. It is possible to continue
the part program at the point of interruption at a later stage.
Definition of interrupt routines
The command SETINT or an interrupt signal via the PI service "ASUB" must be assigned to
a part program, which is supposed to act as interrupt routine. This turns the part program into
an interrupt routine.
Interrupt signals
● A total of eight interrupt signals (inputs) are available.
● All inputs can be controlled via the PLC.
● The first four interrupt signals are also controlled via the four fast NC inputs of the NCU
module.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
K1: Mode group, channel, program operation, reset response
9.10 Asynchronous subprograms (ASUBs), interrupt routines
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