Omron NX-EC0112, User Manual

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5 I/O Refreshing Methods
5 - 8 NX-series Position Interface Units User’s Manual (W524)
 Synchronous Input Refreshing
• The NX Units that operate with synchronous input refreshing in a Slave Terminal read inputs at a
fixed interval based on Sync0. (Refer to figure (a) in the diagram below.)
Refer to the
NX-series EtherCAT Coupler Unit User’s Manual (Cat. No. W519-E1-05 or later) for
information on the Slave Terminals that operate with the same timing when more than one Slave Ter-
minal is placed on the same EtherCAT network.
• The Communications Coupler Unit reads the values that are read by the Units on the input read tim-
ing during the next I/O refresh. (See following figure (b).)
• The I/O refreshing interval changes according to the processing conditions of the Communications
Coupler Unit and host communications master (see following figure (c)), so the input read timing
interval is constant. (See following figure (d), (e).)
• To read the correct input values, the input must be set before the input read timing of the NX Units for
the total time of the ON/OFF response time and input filter time. (See following figure (f).)
Offset between Sync0
and the input read timing
This time is automatically
calculated by the Sysmac Studio.
Constant
Constant
Constant
Constant
(c) The I/O refresh interval is not constant.
Unit A
Unit B
Not constant
I/O refreshing
on NX bus
(d) The Sync0 interval is constant.
ON/OFF response time
Input filter time
(e) Constant
ON/OFF response time
Input filter time
Sync0 Sync0 Sync0
Input refreshing
Output refreshing
(b) During I/O refreshing, the
Communications Coupler Unit reads
the data that was read by the Units.
(f) Input status is
finalized.
(a) All Input Units that operate with
synchronous input refreshing read
their inputs at the same time.