Omron CS1W-ETN21 - Manual (Page 122)

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IP Addresses in FINS Communications Section 5-2
Pairing IP Addresses with
FINS Node Addresses at
Local Nodes A particular IP address is allocated to each communications node, including
Ethernet Units. The IP address must be paired with the FINS node address (1
to 254) by one of the following methods.
Automatic Generation Method (Dynamic/Static)
Set the relation between the IP address and the FINS node address for the
Ethernet Unit according to the following equation. If the setting does not con-
form to this equation, a setting error will be generated and the ERH indicator
will flash.
FINS node address = IP address host number
IP Address Table Method and Combined Method
With these methods, the IP address and the FINS node address for the Ether-
net Unit have no particular relationship. Set both the FINS node address and
the IP address so that they are not duplicated in the network.
Sending Ethernet Unit
FINS Messages When the Ethernet Unit sends a FINS message, it must determine the remote
node's IP address, UDP port number, and TCP port number. The relation-
ships between all addresses, such as remote FINS node addresses and IP
addresses, are managed by an internal table at the Ethernet Unit.
When the Ethernet Unit is turned ON or restarted, the internal table is gener-
ated automatically from the various settings that have been made. Depending
on the setting method used, data such as remote IP addresses are changed
dynamically. (Dynamic changes can be prohibited.)
Remote FINS node
address
Remote IP address
(Example)
Connection Remote port
number (Example)
1 192.168.250.1 UDP 9600
2 192.168.250.2 UDP 9600
to
254 192.168.250.254 UDP 9600
1 192.168.250.1 UDP 9600
2 UDP 9600
! ! !
254 UDP 9600
192.168.250.2
192.168.250.254
FINS header
Remote FINS
node number Remote IP
address (Example) Connection Remote port number (Example)
Internal table
FINS data
Application level
Transport level
Internet level
Physical level
FINS
UDP TCP
IP
Ethernet
Node number
UDP port
number TCP port
number
IP address
Ethernet address
Ethernet V2 IP UDP FINS header FINS data
Remote node
Application level
Transport level
Internet level
Physical level
FINS
UDP TCP
IP
Ethernet
Node number
UDP port
number TCP port
number
IP address
Ethernet address
The remote node's IP address, UDP/TCP
method, UDP port number, and TCP port
number are calculated from the node
number in the FINS message, and an
Ethernet frame is generated.