Mitsubishi Electric QJ71MB91 User Manual page 62

4
MODBUS STANDARD FUNCTIONS
(3) List of MODBUS standard functions supported when accessing a
Table4.3 MODBUS standard function savailable for access to MELSECNET/H remote I/O station
Function
Sub-function
code
Code
(Sub code)
01 -
02 -
03 -
04 -
05 -
06 -
07 -
4
- 7 4.1 MODBUS Standard Function Support List
MELSECNET/H remote I/O station
The following MODBUS standard functions are available when the QJ71MB91
mounted on a MELSECNET/H remote I/O station makes access to the MELSECNET/
H remote I/O station.
Function
Read coils
Read discrete inputs
Read holding registers
Read input registers
Write single coil
Write single register
Read exception status
: Supported
* 1 The access target is the MELSECNET/H remote I/O station.
When the MELSECNET/H remote master station is the access target, available functions are the
same as those shown in (2).
* 2 Accessing the MODBUS device that is not supported by the MELSECNET/H remote I/O station
results in error completion. (Exception code: 04
If the access target is the MELSECNET/H remote master station, it can be assigned to the control
CPU device of the MELSECNET/H remote master station.
Master function
Automatic
MBRW
communication
instruction
function
: Supported with restrictions
)
H
Slave function
MBREQ
instruction
*2
*2
*2
*2
*2
*2
*2
: Not supported
(Continued on next page)
*1