Omron C200HW-CORT21-V1, Operation Manual

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Troubleshooting
Section 7-2
102
Message communication problems (continued)
Description Possible cause Possible remedy
IORD instruction not
executed
successfully. The IORD instruction contains syntax errors.
(EQ-flag is not set) Check if the correct Machine number and
message length is specified in the IORD
instruction.
The control code is invalid or the specified
message length does not correspond with the
function indicated by the control code or
When the local object dictionary is being read,
the object entry to read was never indicated
since power-on or the last reset.
(EQ-flag is not set).
Read the error log to find the cause.
Check if the control code equals #0000 or
#0002.
Check the message length.
In case of reading the local object dictionary,
check if the object entry to read has been
indicated by an IOWR.
The Unit is defective. Replace the C200HW-CORT21-V1.
Not able to access
(read / write) an
object entry. The object entry does not exist or has the
wrong attribute. Read the error log to find the cause.
Check the EDS-file (Appendix A) to see if the
object entry exists. If the object exists, check
the attribute of the object.
To read an object, the attribute must be RO,
RW, RWW, or RWR.
To write to an object, the attribute must be
WO, RW, RWW, or RWR.
The specified data length in the IOWR
message structure does not correspond with
the data length of the object entry. Check the data length of the object entry
User defined CAN
message is not
received by another
node. An incorrect identifier or data length was set in
the IOWR message structure. Compare the identifier of the receiving node
with the one specified in the IOWR message
structure.
Check if the data length corresponds with the
number of data bytes that the receiving node
expects.
The network cabling is not correct. Check the error log. If the error log indicates
that the Unit was unable to transmit the
message, then check if the correct pins of the
bus connector are connected (see section 3-
1-5), if there are no short circuits, if the stub-
lines are not too long, and if the network is
terminated at the appropriate places (see
section 3-3-1).
The receiving node has a 'low-speed' (fault-
tolerant') CAN interface. 'Low-speed' CAN devices use a different
physical layer from the C200HW-CORT21-
V1's 'high-speed' CAN. Converters between
'high-speed' and 'low-speed' CAN are
commercially available.
The Unit operates on a different baud rate than
the other node on the network. Configure all the units on the network to the
same baud rate.