Technical data

Interruptions With the default setting, the TIMED INTERRUPTS level has the
highest priority of the basic levels (can be modified by changing the
parameter assignment in DX 0).
In timed-controlled program execution, the servicing of the delayed
interrupt has highest priority.
Owing to the distribution of priorities, the processing of the delayed
interrupt cannot be interrupted by any other user program.
Special features
•• A delayed interrupt is only processed in the RUN mode. Delayed
interrupts owing in the STOP mode, during
power down or
START-UP are
discarded.
•• A generated delayed alarm (= OB 153 call was processed) is not
retained in the transition to the STOP mode and during POWER
OFF.
•• If you generate a new delayed interrupt, i.e. call OB 153 with
new parameters, a previously set delayed interrupt is cancelled.
A delayed interrupt currently being processed is continued.
This means that only
one delayed interrupt is valid at any one
time.
•• If a delayed interrupt occurs without the previous one being
completely processed, the new interrupt is discarded.
Delayed
interrupts are not checked for collisions!
•• Note the special functions OB 122 and OB 142 with which you
can disable or delay the servicing of delayed interrupts.
RUN Mode
CPU 928B Programming Guide
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