Omron CJ1W-EIP21 ユーザーズマニュアル
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Overview of FINS Communications
Section 8-1
8-1-2
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.
• When FINS nodes are connected on the same Ethernet segment:
Use the FINS/UDP method between those nodes.
Note
FINS/UDP offers a slight advantage in performance.
• When FINS nodes are connected over multiple IP network layers:
Use the FINS/TCP method between those nodes.
Note
FINS/TCP offers superior communications quality.
• When the quality of connections is unreliable, as with wireless LAN:
Use the FINS/TCP method between those nodes.
Note
FINS/TCP offers superior communications quality.
8-1-3
FINS Communications Service Specifications
Item
Specifications
Number of nodes
254
Message length
2,012 bytes max.
Number of buffers
192
Protocol name
FINS/UDP method
FINS/TCP method
Protocol used
UDP/IP
TCP/IP
Number of connections ---
16
Port number
9600 (default)
Can be changed.
Can be changed.
9600 (default)
Can be changed.
Can be changed.
Protection
No
Yes (Specification of client IP addresses when Unit is used as a
server)
server)
Other
Items set for each UDP
port
port
• Broadcast
• IP Address Conversion
• IP Address Conversion
Items set for each connection
• Server/client specification
• Remote IP address specification
• Remote IP address specification
When client: Specify the IP address of the remote Unit (server).
When server: Specify IP addresses of clients permitted to con-
nect.
nect.
• Automatic FINS node address allocation:
Specify automatic allocation of client FINS node addresses.
• Keep-alive:
Specify whether remote node keep-alive is to be used.
TCP/IP Setting
• Remote node keep-alive time
Internal table
This a table of correspondences for remote FINS node addresses, remote IP addresses, TCP/
UDP, and remote port numbers. It is created automatically when power is turned ON to the
PLC or when the Ethernet Unit is restarted, and it is automatically changed when a connection
is established by means of the FINS/TCP method or when a FINS command received.
UDP, and remote port numbers. It is created automatically when power is turned ON to the
PLC or when the Ethernet Unit is restarted, and it is automatically changed when a connection
is established by means of the FINS/TCP method or when a FINS command received.
The following functions are enabled by using this table.
• IP address conversion using the FINS/UDP method
• Automatic FINS node address conversion after a connection is established using the FINS/
• Automatic FINS node address conversion after a connection is established using the FINS/
TCP method
• Automatic client FINS node address allocation using the FINS/TCP method
• Simultaneous connection of multiple FINS applications
• Simultaneous connection of multiple FINS applications