Omron SYSMAC CJ1W-EIP21 - Manual (Page 124)

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IP Addresses in FINS Communications Section 5-2
Example
Combined Method The combined method combines the IP address table method and the auto-
matic generation method (dynamic).
First the IP address table is referenced. Then, if the applicable FINS node
address is found, the corresponding IP address is read. If the FINS node
address is not found, the IP address is calculated using the automatic genera-
tion method (dynamic).
The internal table will be as follows:
• FINS Node Address Registered to IP Address Table
The following address is registered to the internal table.
• Remote IP address: IP address registered in IP address table
• Remote UDP port number: UDP port number set for local Unit
• Connection method: FINS/UDP
• FINS Node Address Not Registered to IP Address Table
The following address is registered to the internal table.
• Remote IP address: Local IP address network number + FINS
node address
• Remote UDP port number: UDP port number set for local Unit
• Connection method: FINS/UDP
With the combined method, records of FINS nodes registered to the IP
address table are not dynamically changed. When the Unit is turned ON or
restarted and the IP address of a remote FINS node is not registered in the IP
table, the IP address can be changed dynamically according to FINS mes-
sages received from the remote node. This can be used effectively when the
remote node is a device such as a personal computer and IP addresses are
dynamically changed by a method such as DHCP.
18
20
23
153.214.0.62
153.214.0.129
153.218.51.8
25 153.218.51.10
When FINS Command is Sent
FINS node number
Node number in
IP address table
IP address table
FINS node
number
IP address
IP address 153.214.0.129
FINS command sent
When FINS Command is Received
FINS node number
Node number not
in IP address table
Changed
Internal table
IP address 153.218.51.10
FINS response returned