Mitsubishi Electronics fx3u user manual 11 - 36

11 - 36
MELSEC-F
TROUBLESHOOTING11
11 - 36
POINT
If the external device communicates normally, the following conditions occur.
For TCP communication
When the external device's open status is complete, LEDs C1, C2, which are in
correspondence with connections 1, 2, turn on.
For UDP communication
When external device communication is possible, LEDs C1, C2, which are in
correspondence with connections 1, 2, turn on.
Was the "0001H" written to
from BFM#1610, 1611?
NO
YES
Is the word
count (procedure) or byte
count (non-procedure) set at the
head of the fixed
buffer?
NO
YES
Check the communication status of
the external device.
1)
Correct the write condition of
BFM#1610, 1611.
Write the data length.
NO
YES
Check the fixed buffer transfer error
code of BFM#125, 135
Does the external
device operate normally? NO
YES
Fix the faulty part of the external
device. (If the receiving side is also an
Ethernet module, see Section 11.4.)
Are there any
open errors or initial errors
in the error log area?
NO
YES
Check and fix the faulty part.
The Ethernet module hardware on the
sending side may be faulty.
Consult your nearest branch office or
dealer with the details of the errors.
Is the read value of
BFM#1610, 1611 "0004H"?
Does the
communication protocol
(TCP/UDP) match that of
the external device?
NO
YES
Match the protocol with the
communication protocol (TCP/UDP) of
the external device. (For details, see
Section 5.5.)