Omron SYSMAC CP Series, User Manual

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11 High-speed Counters
11-2
CP2E CPU Unit Software User’s Manual(W614)
11-1 Overview
High-speed counters can be used with any model of CP2E CPU Unit.
High-speed counters are used to measure high-speed pulse input signals that cannot be measured by
counter (CNT) instructions.
z
Applications
• Detecting the position or length of a workpiece with an input from an incremental rotary encoder.
• Measuring the speed of a workpiece from its position data using frequency measurement and
rotational speed conversion.
• High-speed processing according to the workpiece ’ s position data.
The present value of the high-speed counter is stored in the Auxiliary Area and can be used as posi-
tion data. When it reaches preset values, interrupts can be generated. The count can be started and
stopped. Depending on the instruction, the frequency (speed) can be read from the present value of
the high-speed counter.
11-1-1 Overview
Encoder
· Phase A/phase B
· Up/do
w n p u lse inp u ts
· Reset inp u t (phase Z)
Etc.
High-speed co u nter PV
(stored in A u xiliary Area)
Changes to PV
Target v al u e comparison
Interr u pt task
· Reading PV (from A u xiliary Area
or u sing PRV instr u ction)
· Reading fre qu ency ( u sing PRV instr u ction)
· Setting target v al u es or range u pper/lo w er
limits and starting comparison, specifying
interr
u pt task to b e started
Read
PRV
CTBL
Co u nt
inp u t
High-speed co u nter PV comparison
Read
Settings
Range comparison for
u pper and lo w er limits