Omron NX-EC0112, Руководство пользователя

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5 I/O Refreshing Methods
5 - 10 NX-series Position Interface Units User’s Manual (W524)
With task period prioritized refreshing, shortening the task period is given priority over synchronizing the
I/O timing with other NX Units that use synchronous I/O refreshing.
 Input Prioritized Refreshing
• The Communications Coupler Unit performs I/O processing so that the input values of NX Units
are read during the next I/O refresh. (See following figure (a).)
• The I/O refreshing interval changes according to the processing conditions of the Communica-
tions Coupler Unit and host communications master (see following figure (c)), so the inputs are
read at the next I/O refresh. (See following figure (b).)
• Because input processing is given priority, output processing is performed after input processing
is completed. (See following figure (d).)
*1. The timing of I/O is given as an example. The actual timing will vary.
Operation for Task Period Prioritized Refreshing
Sync0 Sync0 Sync0
Constant Constant
Constant Constant
(c) The I/O refresh interval is not constant.
Not constant
I/O refreshing on NX bus
The Sync0 interval is constant.
Constant
The Sysmac Studio
automatically calculates the
offset between Sync0 and
the input read timing.
Unit A with synchronous
I/O refreshing
Unit B with synchronous
I/O refreshing
Incremental Encoder Input
Unit
*1
SSI Input Unit
*1
Output value
Output value Output value
Output value
Input status is
finalized.
(d) The data is output after input
processing is completed.
(a) Reading inputs is given priority.
(b) During I/O refreshing, the
Communications Coupler Unit reads
the data that was read by the Units.
Output refreshing
Input refreshing