Omron NX-ILM400, User Manual

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5 I/O Refreshing
5 - 2 NX-series IO-Link Master Unit User’s Manual (W567)
5-1 I/O Refreshing
This section describes I/O refreshing for the NX Units.
An NX-series NX1P2 CPU Unit refreshes the I/O for NX Units cyclically.
The following period and two cycles affect operation of the I/O refreshing between the CPU Unit and the
NX Units:
(a) Primary period in CPU Unit
(b) Refresh cycle of the NX bus
(c) Refresh cycle of each NX Unit
The following operations are performed.
• The refresh cycle of the NX bus in item (b) is automatically synchronized with the primary period of
the CPU Unit in item (a).
• The (c) refresh cycles of the NX Units depend on the I/O refreshing methods, which are described
later.
Refer to the NJ/NX-series CPU Unit Software User’s Manual (Cat. No. W501-E1-16 or later) for infor-
mation on refreshing of I/O between an NX-series NX1P2 CPU Unit and NX Units.
Refer to the NJ/NX-series CPU Unit Software User’s Manual (Cat. No. W501-E1-16 or later) for details
on I/O response times for NX Units on CPU Racks.
The CPU Unit or the Industrial PC performs I/O refreshing cyclically with the Slave Terminals through
the Communications Master Unit and the Communications Coupler Unit.
The following four cycles affect operation of the I/O refreshing between the CPU Unit or the Industrial
PC and the NX Units in a Slave Terminal:
(a) Cycle time of the CPU Unit or Industrial PC
(b) Communications cycle of the host network
5-1-1 I/O Refreshing from the CPU Unit to NX Units
5-1-2 I/O Refreshing from the CPU Unit or Industrial PC to Slave Termi-
nals
CPU Unit
(b)
NX Unit NX Unit
(c) (c) (c)
NX Unit
(a)
Data exchange between
the user program and I/O Units