A - 43
  Appendices
NX-series EtherNet/IP Coupler Unit User’s Manual (W536)
A-2  TCP/UDP Message Service
A
A-2-6  Troubleshooting Errors Related to the TCP/UDP Message Service
Refer to A-2-4 TCP/UDP Message Service Specifications on page A-38 for information on 
TCP/IP port number and UDP/IP port number setting ranges.
Use the following information to determine the cause and corrective actions of problems in the 
TCP/UDP message service.
A-2-6 Troubleshooting Errors Related to the TCP/UDP Message Ser-
vice
Observation General status Cause Corrective action
Reading or writing data 
is not possible. 
An error response is 
returned by the Ether-
Net/IP Coupler Unit.
NOT_ENOUGH_DATA 
(0x13)
The total frame size is 
larger than 504 bytes.
The data-field size value 
does not match the actual 
received frame size.
Ensure the frame size field is 
correctly calculated.
Refer to A-2-4 TCP/UDP 
Message Service Specifica-
tions on page A-38 for more 
information.
TOO_MUCH_DATA 
(0x15)
The data field size value 
does not match the actual 
received frame size.
Other error codes
---
Refer to A-1 Supported CIP 
Objects on page A-3 and 
General Status Code on page 
A-30.
Reading or writing data 
is not possible. 
No error response is 
returned by the Ether-
Net/IP Coupler Unit.
---
The frame length is 
smaller than the minimum 
frame length of 12 bytes.
Ensure the size of the frame 
is within specifications.
---
The data field size value 
does not match the actual 
transmitted number of 
bytes.
Ensure the size of the frame 
is the same as the specified 
number of bytes in the data 
field.
---
Unstable network commu-
nications.
Check network connections 
and other sources of interfer-
ence. 
Refer to Section 7 Ether-
Net/IP Network Wiring for 
more information.
---
The TCP/UDP message 
service has not been 
enabled in the EtherNet/IP 
Coupler Unit. (Tag data 
links are enabled.)
Check the position of DIP 
switch pin 3.
Refer to 4-3-2 DIP Switch on 
page 4-9 for more informa-
tion.
---
The frame is sent to an 
EtherNet/IP Coupler Unit 
with an incorrect port 
number setting.
Check the port number set-
ting.
Refer to A-2-5 TCP/IP and 
UDP/IP Port Number Setting 
on page A-41.
An unexpected frame 
size restriction violation 
occurred during usage of 
the TCP/UDP message 
service.
---
The MTU/maximum data-
gram size is less than the 
required frame length.
Ensure the maximum frame 
size is the same or less than 
the maximum allowed data-
gram size on the client.