Omron NX-EC0112, User Manual

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6 Incremental Encoder Input Units
6 - 70 NX-series Position Interface Units User’s Manual (W524)
You can measure the period between the rising edges or falling edges of the input pulse.
For phase-A input pulses, the rate of change of the specified edge is measured and the most recent
measurement result for the latest NX bus I/O refresh is returned.
This measurement is not performed in sync with the NX bus synchronization cycle.
 Example Operation for Measuring Both Edges
*1. The pulse period measurement counter retains the most recent value while the function is disabled.
*2. The operation is reset if the Overflow Flag is ON when the function is disabled.
6-9-11 Pulse Period Measurement
Item Specifications Remarks
Measurement target Phase-A input pulse Measures the pulse frequency according to the
specifications listed in the column to the left, regard-
less of the pulse input method, counting direction, or
multiplier.
Detection method • Between rising edges
• Between falling edges
• Between both edges
Measurable range 1 to 4,294,967,295 (
×
100 ns)
(100 ns to 429.4967295 s)
The data type is UDINT.
However, frequency measurements that exceed the
maximum response frequency may not be accurate.
If the maximum measurable value is exceeded, the
value returns to zero.
Measurement resolution
(minimum measurement
unit) 100 ns Times below 100 ns are rounded up.
4,294,967,295
0
aaa bbb
ccc
Phase-A input pulse
ddd
Output (CPU Unit to Unit)
Input (Unit to CPU Unit)
Pulse Period Measure-
ment Enable bit
Pulse Period Measure-
ment Enabled
Started. Restarted. Started.
Time
Pulse Period Measurement Value Clear bit
Pulse Period Measurement Value
Overflow Flag Clear bit
Pulse Period Measured Value
0 aaa bbb 0 0
Pulse Period Measurement
Value Clear Completed bit
Pulse Period Measurement
Value Overflow Flag
ccc ddd
Pulse period
measurement
started. Pulse period
measurement value
overflow occurred.
Pulse Period
Measurement Value
Clear executed.
Pulse period
measurement value
overflow occurred.
Pulse Period
Measurement Value
Overflow Flag Clear
executed.
Pulse period
measurement
stopped.
Pulse period
measurement
started.
(*1)
(*2)