Omron CP1H CPU UNITS - PROGRAMMING 05-2007, Руководство по эксплуатации

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High-speed Counters
Section 5-2
• When a high-speed counter is being used (enabled in the PLC Setup), the
input cannot be used as a general-purpose (normal) input, interrupt input,
or quick-response input.
Starting Interrupt Tasks based on Comparison Conditions
Data registered in advance in a comparison table can be compared with the
actual counter PVs during operation. The specified interrupt tasks (registered
in the table) will be started when the corresponding comparison condition is
met.
There are two comparison methods available: Target value comparison and
range comparison.
• Use the CTBL(882) instruction to register the comparison table.
• Use either the CTBL(882) instruction or INI(880) instruction to start the
comparison operation.
• Use the INI(880) instruction to stop the comparison operation.
Target Value Comparison The specified interrupt task is executed when the high-speed counter PV
matches a target value registered in the table.
• The comparison conditions (target values and counting directions) are
registered in the comparison table along with the corresponding interrupt
task number. The specified interrupt task will be executed when the high-
speed counter PV matches the registered target value.
• Up to 48 target values (between 1 and 48) can be registered in the com-
parison table.
• A different interrupt task can be registered for each target value.
• The target value comparison is performed on all of the target values in the
table, regardless of the order in which the target values are registered.
• If the PV is changed, the changed PV will be compared with the target
values in the table, even if the PV is changed while the target value com-
parison operation is in progress.
Restrictions
A comparison condition (target value and count direction) cannot appear in
the table more than once. An error will occur if a comparison condition is
specified two or more times.
Note When the count direction (incrementing/decrementing) changes at a PV that
matches a target value, the next target value cannot be matched in that direc-
tion.
No. 001 No. 015 No. 000 No. 020
High-speed counter PV
Comparison is
executed without
regard to the order
of the values in the
table.
Target value 1
Target value 2
Target value 3
Target value 4
Interrupt task that is started.
Time
Comparison table
Number of values = 4
Target value 1 (Incrementing)
Interrupt task = 000
Target value 2 (Incrementing)
Interrupt task = 001
Target value 3 (Decrementing)
Interrupt task = 020
Target value 4 (Incrementing)
Interrupt task = 015