Mitsubishi QJ71MB91, User Manual

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4
- 43 4.11 Diagnostics (FC: 08)
4.11.15 Return IOP overrun error count (sub-function code: 19)
4
MODBUS(R) STANDARD FUNCTIONS
4.11.15 Return IOP overrun error count (sub-function code: 19)
Reads the IOP overrun error counter value to the master.
The QJ71MB91 returns to the master the number of times the request message size
exceeds the upper limit.
(Same as the Return bus character overrun count)
(1) Request message format (Master Slave)
(2) Response message format (Slave Master)
(When completed normally)
* 1 Refer to the following for the relevant counts, count clear methods and precautions.
Section 11.3
(When completed with an error)
* 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
Figure 4.66 Return IOP overrun error count (Request message)
Figure 4.67 Return IOP overrun error count (Normal response message)
Figure 4.68 Return IP overrun error count (Exception message)
(L)
Data
(L)
Function code
Function
code
(08
H
)
Sub-function code
Sub-function code
(0013
H
)
(0000
H
)
(H) (H)
(L)
Data
(L)
Function code
Function
code
(08
H
)
Sub-function code
Sub-function code
(0013
H
)
Bus character
overrun count value
(0000
H
to FFFF
H
) *
1
The QJ71MB91 returns the bus character overrun count value
of the buffer memory to the master. (address: 0F02
H
/0F42
H
)
(H)
(H)
Data
Function code
Function
code
(88
H
)
Exception
code * 2