Toshiba V Series, User Manual

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Ethernet module User’s Manual
Chapter 8 Error Handling
8
(7) When Transmission Using TCP Sockets Fails
When troubleshooting TCP sockets, also refer to the "TCP Socket Notes" section.
(a) Open request
Start
Refer to the completion status
and eliminate the cause of the
error.
Is the URCV_T
instruction completed ?
A timeout occurred ?
Error status --- 2848
No
Yes
Yes
Confirm the status when the
USEND_T or URCV_T is not
completed.
Is the station status
such that run + socket
transmission is
enabled ?
Set the station to run + socket
transmission enabled using an
operating mode control request.
Is the waiting time set
to unlimited ?
No
No No
Yes
Yes
①
①
End
Verify the remote node IP address
and UDP port number.
1) Check the slave station IP address
and message transmission UDP
port number again.
2) Configure the router if there is a
router on the transmission line.
3) Check the network verification
items.
Are the remote node
IP address and UDP port
number correct ?
No
Yes
Decide which role each socket will
play when establishing a connection
between a pair of sockets.
Is the program
attempting to issue an active
open to a socket in the passive
open state ?
No
Yes
No
Yes
Does a response come
back if a PING is issued to the
remote station ?
No
Yes
Is the error counter
read out from the RAS information
constant ?
RAS error counters: Alignment error
Short packet, CRC error
It is possible that there is an error on
the network itself. Check the network
verification items.