Data Cannot Be Sent With Communications Using A Fixed Buffer - Mitsubishi Electric MELSEC-L SERIES Basic User Manual

16.6.8
Data cannot be sent with communications using a fixed
buffer.
The following table lists how to troubleshoot the problem when an E71 cannot send data with communications using a
fixed buffer.
Check item
Has the connection with the connected device been opened?
(Check the corresponding bit of 5000
Is the IP address setting of the connected device correct?
Does the communication protocol (TCP/IP or UDP/IP) match
with that of the connected device?
Was the BUFSND instruction executed?
Was the BUFSND instruction completed normally?
Has the data length of the send data been set in the control
data?
Is the communication status of the connected device
normal?
Has an open or initial error occurred in the error log area?
If the action above does not solve the problem, perform the following tests on the E71 to check for hardware error.
• Hardware test (
• Self-loopback test (
• Open the connection with the connected device.
• Check if the open/close processes for I/O signals and the OPEN/CLOSE
instructions are not used together for the same connection. If so, correct
in the buffer memory.) the program.
H
• Read Open error code (address: 7C
storage area. Then check the error details and correct the error.
Check and correct the IP address of the connected device.
Use the same communication protocol (TCP/IP or UDP/IP) as that of the
connected device.
• Correct the execution conditions of the BUFSND instruction.
• Check if the send/receive process for I/O signals and the
BUFSND/BUFRCV instructions are used together for the same
connection. If so, correct the program.
Check the error code in the BUFSND instruction completion status area
and correct the error.
Write the data length.
Correct the error in the connected device.
Check and correct the error.
Page 333, Appendix 6.2)
Page 332, Appendix 6.1)
CHAPTER 16 TROUBLESHOOTING
Action
) in the communication status
H
16
251