Azbil C7G User Manual

8-4
Chapter 8. Modbus TCP Communication Functions
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Exception code
In the case of a response message when there was an error, one of the exception
codes shown below is put after the function code.
Error type Exception code Description
Illegal function code "01" (2 bytes) Function code not supported by this controller
Illegal data address "02" (2 bytes) A data address that could not be read or written was
included
Illegal data "03" (2 bytes) Error other than those shown above
BUSY "06" (2 bytes) This device cannot process the data. Please send again.
The table below shows the processing related to illegal data addresses.
Start data
address
Second and later
data addresses
Exception code Message processing
Correct All correct Exception code for
illegal data address
is not added.
For a read command, all the data is read.
For a write command, all the data is written.
Correct Incorrect address is
included.
For a read
command, no
illegal data address
exception code is
added.
For a write
command, the
illegal data address
exception code is
added.
For a read command, data is read for
the correct addresses, and the values of
incorrect addresses are read as 0.
For a write command, data is written for
correct addresses and is not written for
incorrect addresses.
Incorrect All correct Exception code for
illegal data address
is added.
For a read command, data is not read.
For a write command, data is written for
correct addresses and is not written for
incorrect addresses.
Incorrect Incorrect address is
included.
If the version of the MAIN block firmware is earlier than 6.x.x (where x stands for
any number), the processing related to illegal data addresses is as shown in the table
below.
Start data
address
Second and later
data addresses
Exception code Message processing
Correct All correct Exception code for
illegal data address
is not added.
For a read command, all the data is read.
For a write command, all the data is written.
Correct Incorrect address
is included.
Exception code for
illegal data address
is added.
For a read command, data is not read.
For a write command, data is not written.
Incorrect Incorrect address
is included.
Incorrect All correct

Azbil C7G Specifications

General

Brand	Azbil
Model	C7G
Category	Controller
Language	English