Omron SYSMAC NX-CIF101 User Manual

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7 Serial Communications
NX-series Communications Interface Units User’s Manual (W540)
7-8 Communications Performance
7
7-8-1 Calculating the Communications Performance
7-8 Communications Performance
This section describes how to calculate the communications performance of the CIF Unit. You can
adjust the divided data sizes to improve communications performance.
The communications performance is determined by the tran
sfer time between the CPU Unit or commu-
nications master and CIF Unit and the transfer time
between the CIF Unit and serial line.
The calculation formulas for the transfer time betwee
n the CPU Unit or communications master and CIF
Unit and the transfer time between the CIF Unit and serial line are given for the following three cases.
• Data send times when transmission buffering is enabled
• Data send times when transmission buffering is disabled
• Data reception time
One of the elements of communications performance is t
he I/O refreshing cycle. The I/O refreshing
cycle depends on the system configuration as given below.
Precautions for Correct Use
The values found with the calculation formulas for the communications performance are only
guidelines. Actual transfer times will vary. Always test performance with the actual equipment
before you use the system.
7-8-1 Calculating the Communications Performance
System configuration I/O refresh cycle
• CPU Unit connection
• NJ/NX-series CPU Unit or NY-series Industrial PC and
EtherCAT Coupler Unit connection
Task period of the primary periodic task
NJ/NX-series CPU Unit or NY-series Industrial PC and
Eth
erNet/IP Coupler Unit connection
Cycle of the task where the user program that con-
trols the CIF Unit is allocated plus the packet inter-
val (RPI) of tag data links
Communications master other than an NJ/NX-series CPU
Unit or NY-ser
ies Industrial PC and EtherNet/IP Coupler
Unit connection
Maximum cycle time plus the pack
et interval (RPI)
of tag data links
Receive buffer
Send buffer
Serial communi-
cations device
CIF Unit
CPU Unit or communications
master
The communications performance is determined by these two transfer times.
NX bus or
communica-
tions cable
Serial line

Omron SYSMAC NX-CIF101 Specifications

General

Brand	Omron
Model	SYSMAC NX-CIF101
Category	Recording Equipment
Language	English