User interfaces
OB 10 to OB 18
When a timed interrupt occurs, the corresponding organization block
is called as the user interface at the next block boundary (or operation
boundary).
For example, you would program the routine to be inserted in cyclic
program execution every 100 ms in OB 10 (default).
The timed interrupt is only processed if the assigned organization
block is loaded. If none of the organization blocks OB 10 to OB 18
are loaded, there is no time-controlled program execution and the
cyclic program is not interrupted.
You can disable the execution of timed interrupts by setting a
parameter in data block DX 0, e.g. for testing your program.
Interruptions
As default, the TIMED INTERRUPTS level has the highest priority of
the basic levels (can be modified in DX 0).
Owing to the distribution of priority within time-controlled program
execution, the following interruptions in the processing of a cyclic
timed interrupt are possible:
••
the processing of a cyclic timed interrupt can be interrupted by the
processing of a delayed interrupt
••
organization blocks with shorter time bases have higher priority
and can interrupt organization blocks with longer time bases (e.g.
OB 12 can interrupt OB 17).
Note
With the three shortest time bases (OB 10 to 12) multiple
processing without interruption is possible. If, for example, while
OB 10 is being processed, a further timed interrupt for OB 10
occurs, the currently active processing of OB 10 is first
completed. Following this, OB 10 is called immediately again. If,
however, there are more than three timed interrupts pending for
one of the time bases, a collision of timed interrupts error occurs.
RUN Mode
CPU 948 Programming Guide
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C79000-G8576-C848-04
Summary of Contents for CPU 948
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Page 32: ...Contents CPU 948 Programming Guide 2 2 C79000 G8576 C848 04 ...
Page 72: ...Data Blocks CPU 948 Programming Guide 2 42 C79000 G8576 C848 04 ...
Page 74: ...Contents CPU 948 Programming Guide 3 2 C79000 G8576 C848 04 ...
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Page 308: ...Contents CPU 948 Programming Guide 7 2 C79000 G8576 C848 04 ...
Page 324: ...Examples of Parameter Assignment CPU 948 Programming Guide 7 18 C79000 G8576 C848 04 ...
Page 326: ...Contents CPU 948 Programming Guide 8 2 C79000 G8576 C848 04 ...
Page 370: ...Addressable System Data Area CPU 948 Programming Guide 8 46 C79000 G8576 C848 04 ...
Page 372: ...Contents CPU 948 Programming Guide 9 2 C79000 G8576 C848 04 ...
Page 486: ...Contents CPU 948 Programming Guide 11 2 C79000 G8576 C848 04 ...
Page 522: ...PG Functions via the S5 Bus CPU 948 Programming Guide 11 38 C79000 G8576 C848 04 ...
Page 524: ...Contents CPU 948 Programming Guide 12 2 C79000 G8576 C848 04 ...
Page 538: ...Contents CPU 948 Programming Guide 13 2 C79000 G8576 C848 04 ...
Page 546: ...List of Key Words CPU 948 Programming Guide Index 6 C79000 G8576 C848 04 ...