Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual page 302

Socket communications/communications using the fixed buffer cannot be performed.
When socket communications or communications using the fixed buffer cannot be performed, check the following items and
take action.
Check item
Has the connection with the external device been opened? (Check 'Open
completion signal' (Un\G1900000 to Un\G1900007)
Has the send/receive processing been executed properly?
Does 'Socket/fixed buffer reception status signal' (Un\G1900016 to
Un\G1900023) turn on when receive processing is executed?
Is the communication method of the connection used for communication with
the external device is set to an item other than the following in the "External
Device Configuration" window of "Basic Settings"?
• Socket communications: "Socket Communication"
• Communications using the fixed buffer: "Fixed Buffer (Procedure Exist)" or
"Fixed Buffer (No Procedure)"
Is the communication method of the connection used for communication with
the external device is set to an item other than "Broadcast Send" or
"Broadcast Receive" in the "External Device Configuration" window of "Basic
Settings" when broadcast communications is performed?
If the above action does not solve the problem, perform the module communication test to check for hardware failure. (
Page 284 Module communication test)
*1 The buffer memory address is for when the network type of the RJ71EN71 or the RnENCPU (network part) is set to "Ethernet" and the
P1 connector is used.
When using the P2 connector or the CPU module (built-in Ethernet port part), or setting the network type to "Q Compatible Ethernet",
refer to the following.
Page 336 Buffer Memory
*2 If the connection of only the external device is closed due to cable disconnection, personal computer restart, or other reasons, reopen
the connection using the same port used before the error occurred. The E71 does not close a connection if it receives an Active open
request again from the external device with a different IP address or a port number.
*3 The module communication test cannot be performed for the CPU module (built-in Ethernet port part). Perform the troubleshooting of
the CPU module and check for hardware failure. ( MELSEC iQ-R CPU Module User's Manual (Startup))
3 TROUBLESHOOTING
300
3.4 Troubleshooting by Symptom
Action
• If the connection with the external device is not opened, perform the open
*1*2
• If an error occurs, check and eliminate the error cause.
• If the send/receive processing has not been executed, check and correct
• If send/receive processing has completed with an error, check the error
• Send data from the external device.
• If data has been sent, check that the destination address (IP address and
Correct the communication method setting if an item other than the one
described in the left is set. ( Page 244 External Device Configuration)
Correct the communication method setting if an item other than the one
described in the left is set. ( Page 244 External Device Configuration)
*3
processing.
the execution condition of the send/receive processing.
code in the completion status and eliminate the error cause.
port number) is correctly set.