Return Bus Communication Error Count (Sub-Function Code: 12) - Mitsubishi Electric QJ71MB91 User Manual

4
MODBUS STANDARD FUNCTIONS

4.11.8 Return bus communication error count (sub-function code: 12)

Reads out the number of error messages detected on the line to the master.
(1) Request message format (Master
(2) Response message format (Slave
(When completed normally)
Function code
Figure 4.46 Return bus communication error count (Normal response message)
(When completed with an error)
Figure 4.47 Return bus communication error count (Exception message)
Function code Sub-function code
Sub-function code
Function
code (000C
H
(08 )
H
(H)
Figure 4.45 Return bus communication error count (Request message)
Sub-function code
Function
Sub-function code
code
(000C )
H
(08 )
H
(H)
The QJ71MB91 returns the bus communication error count value
of the buffer memory to the master. (address: 0F01
* 1 Refer to the following for the relevant counts, count clear methods and precautions.
Section 11.3
Function code Data
Function
Exception
code
2
code *
(88 )
H
* 2 Exception and error codes are stored in the buffer memory in the case of error completion.
Refer to the following for storage location, confirmation methods, and detailed contents.
Section 11.4
4.11.8 Return bus communication error count (sub-function code: 12)
Slave)
Data
) (0000 )
H
(L)
(H)
Master)
Data
Bus communication
error count value
(0000 to FFFF
H
(L)
(H)
/0F41
H H
4.11 Diagnostics (FC: 08)
(L)
1
) *
H
(L)
)
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