5 I/O Refreshing
5 - 2
NX-series Analog I/O Units User’s Manual for Analog Input Units and Analog Output Units (W522)
5-1
I/O Refreshing
This section describes I/O refreshing for NX Units.
An NX-series NX1P2 CPU Unit cyclically performs I/O refreshing with the NX Units.
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 operation occurs.
• 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 refresh cycle of each NX Unit in item (c) depends on the I/O refreshing method which is given
below.
Refer to the
NJ/NX-series CPU Unit Software User's Manual
(Cat. No. W501-E1-16 or later) for detailed
information on I/O refreshing between the NX1P2 CPU Unit and the NX Units.
Refer to the
NJ/NX-series CPU Unit Software User's Manual
(Cat. No. W501-E1-16 or later) for the I/O
response times of NX Units in a CPU Rack.
5-1-1
I/O Refreshing from CPU Units to NX Units
CPU Unit
(b) Refresh cycle of the NX bus
NX Unit
NX Unit
(c) Refresh cycle of each NX Unit
NX Unit
(a) Primary
period in CPU
Unit
Data exchange between
the user program and I/O Units
Summary of Contents for NX-AD series
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