Technical data

If a process interrupt and a time interrupt occur simultaneously the
process interrupt is processed first at the next interrupt point. After
this is completed, the pending time interrupt is then processed.
Fig. 4-9 is a schematic representation of how program execution is
interrupted at block boundaries by time-controlled and
program-controlled interrupt processing.
cyclic
OB 1 PB
Interrupt point at which
interrupt or time-driven
program execution can
normally be inserted
into cyclic, interrupt or
time-driven program
execution. Time-driven
program execution can
only be interrupted by
a process interrupt and
not vice-versa.
interrupt-driven
OB 2
time-driven
OB 9/OB 13
Fig. 4-9 Interrupt-driven program execution at block boundaries
4
RUN Mode
CPU 928B Programming Guide
C79000-B8576-C898-01
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