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6 Incremental Encoder Input Units
NX-series Position Interface Units User’s Manual (W524)
6-9 Functions
6
6-9-12 Time Stamping
When you obtain position data from an Incremental Encoder Input Unit and the position data has
changed from the previously obtained position data, you can obtain the DC time when that change
occurred along with the data.
Position data is obtained when NX bus I/O is refreshed.
The obtained position data and DC time are input to the Controller.
The obtained DC time is called a time stamp.
If there was no change in the position data, the time stamp is not updated and so the previous time
stamp is retained.
Refer to 6-7-1 Data Items for Allocation to I/O on page 6-34 for information and Time Stamp on page
6-40 for details on time stamps.
If you use time stamping, you must assign a time stamp to I/O in the Incremental Encoder Input Unit.
Time stamps are not assigned by default.
Add a time stamp to the I/O entries in the I/O entry mapping using the I/O assignments of the Incremen-
tal Encoder Input Unit.
Refer to the NX-series EtherCAT Coupler Unit User’s Manual (Cat. No. W519) for details.
Refer to Operation of Synchronous I/O Refreshing on page 5-7 for information on refreshing of NX bus
I/O.
Precautions for Correct Use
• An EtherCAT Coupler Unit with unit version 1.1 or later is required.
• Time stamping is supported only when synchronous I/O refreshing is used. When Free-Run
refreshing is used, the data will always be 0.
6-9-12 Time Stamping
Position data
I/O refreshing
on NX bus
DC time
obtained.
DC time
obtained.
DC time
obtained.
DC time not
obtained.