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2  PARAMETER SETTINGS
2.2  Basic Settings
*1 When "Q Compatible Ethernet" is selected in the network type, the setting range is 1 to 16.
*2 This setting is not available for the CPU module (built-in Ethernet port part).
*3 This setting is not available when the RJ71EN71 network type is set to "Q Compatible Ethernet".
*4 When the automatic detection of the connected devices is executed, the values read from the connected devices will be the default.
*5 When "Communication Method" is set to "OPS Connection", 255.255.255.255 can be set.
Comment can be set on the "Properties" window displayed by right-clicking the module in "List of devices" or 
"Device map area" and selecting "Properties". The following can be performed depending on the selected 
device.
 • Changing the image
 • Creating association with a file or application
■Existence Confirmation
When the Ethernet-equipped module has not communicated with the external device for a certain period of time while the 
connection is open, this function checks whether the external device is alive by sending an alive check message to the device 
and waiting for the response.
The following table lists the details on alive check.
*1 The connection may be disconnected if the external device does not support the TCP KeepAlive function (response to a KeepAlive ACK 
message).
*2 The Ethernet-equipped module automatically sends an echo response packet when it receives a PING echo request command. (It 
sends a response to the received PING command even if the connection used in the data communications with the external device is 
closed.)
If a response message cannot be received from the external device (or if an error has been detected) using the alive check 
function, the following are performed.
 • The corresponding connection will be forcibly closed. (The line is disconnected.) Open the connection again using a user 
program.
 • Open completion signal is turned off, and the error code is stored in the buffer memory areas.
Existence Confirmation Select the method of alive check which is performed when the 
Ethernet-equipped module has not communicated with the external 
device for a certain period of time. When the module cannot 
communicate with the external device, the connection will be closed. 
( Page 246 Existence Confirmation)
• KeepAlive
• UDP
• Do not confirm existence
Item Applicable protocol Description
KeepAlive TCP/IP This method is used for a connection opened using TCP/IP. The Ethernet-equipped module performs 
an alive check by sending an alive check ACK message to the external device with which 
communications have not been performed for a certain period of time and waiting to see whether the 
response is received.
The connection will be automatically closed when the open state is not continued.
*1
UDP UDP/IP This method is used for a connection opened using UDP/IP. The Ethernet-equipped module performs 
an alive check by sending the PING command (ICMP echo request/response function) to the external 
device with which communications have not been performed for a certain period of time and waiting to 
see whether the response is received.
*2
Do not confirm existence TCP/IP, UDP/IP Alive check is not performed.
Item Description Setting range