Omron CS1W-ETN21 - Manual (Page 139)

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Overview of FINS Communications Section 6-1
6-1 Overview of FINS Communications
6-1-1 Communications On an Ethernet Network
Data is sent and received as UDP/IP packets or TCP/IP packets on an Ether-
net network.
In the FINS communications service, both an IP address for IP (the Internet
layer) and a FINS node address for FINS (the application layer) are used for
the remote device. Also, 9600 is used as the default setting for the local UDP
or TCP port number (i.e., the transport layer) for identifying the application
layer, i.e., the FINS communications service. (Another number can be set for
the FINS/UDP port from the Setup Tab in the Unit Setup.)
For details on pairing FINS node addresses with IP addresses and UDP/TCP
port numbers, refer to 5-2 IP Addresses in FINS Communications.
The FINS communications service is a communications method based on
UDP/IP, and it is supported by most OMRON Ethernet-related products. (In
this manual it is called the FINS/UDP method.) In addition to supporting the
FINS/UDP method, the CS1W-ETN21 and CJ1W-ETN21 support FINS com-
munications using TCP/IP. (In this manual, this is called the FINS/TCP
method.)
6-1-2 Using the FINS/UDP and FINS/TCP Methods
It is recommended that FINS/UDP and FINS/TCP be used as follows:
• When remote devices do not support the FINS/TCP method:
Use the FINS/UDP method for FINS communications with those devices.
Packet (FINS command)
Ethernet
Packet (FINS response)
Ethernet Unit
PLC
PLC
Ethernet Unit
or host computer
FINS
UDP TCP
IP
Ethernet
Ethernet Address
Node Number
Application Layer
Transport Layer
Internet Layer
Physical Layer
IP Address
UDP Port No. TCP Port No.