Mitsubishi QJ71MT91 User Manual page 216

10 DEDICATED INSTRUCTIONS
Type Specification of the Target MODBUS
Set
Read target
values
0100 Coil
H
0200 Input
H
0400 Input register
H
0500 Holding register
H
0700 Extended file register
H
0001
H
No specification
0005
H
0007
H
0505 Holding register
H
10 - 5
*4: Set "0" for the case of write only.
*5: Set "0" for the case of read only.
*6: The combinations of the read and write targets that can be set in the target
MODBUS device type setting and the setting ranges of the access points are
R
as indicated in the following table.
Device
R
Write target
No specification
Coil
Holding register
Extended file register
Holding register
1) No combination setting other than the above is allowed for the type
specification of the target MODBUS
2) Simultaneous execution of read and write with a single instruction is
allowed only for 0505
3) Read file record (FC: 20) and Write file record (FC: 21) allows access to
multiple areas in one communication, however, only one area is accessible
in one communication when using this dedicated instruction.
POINT
(1) When the close option setting of the execution type ((S1)+0) is "TCP connection is closed
after instruction completion", TCP connection is closed after the dedicated instruction
has been completed and the completion device (D2) has turned ON.
If the dedicated instruction is executed again for the same target device during this TCP
connection closing processing, it is completed with an error.
When the execution interval of the dedicated instruction for the same target device is
short, set the close option to "TCP connection is not closed after instruction completion".
(2) Specify "(device number) - 1" as the device number.
However, this does not apply to the file number and device number specified for the
Read/write file record.
(3) When access is made to the bit device (coil, input) of the slave, the fraction bit is handled
as described below.
[Read]
When the read access points are 35 points
<Read data storing device (D1)>
to
bF
D100
D101
D102
Remaining area is masked by 0.
[Write]
When the write access points are 5 points
<Write data storing device (S2)>
to
bF
D300
Remaining area is ignored.
Function Code
01 Read coils
02 Read discrete inputs
04 Read input registers
03 Read holding registers
20 Read file record
15 Write multiple coils
16 Write multiple registers
21 Write file record
23 Read/write multiple registers
device ((S1)+8).
R
(Read/Write Multiple Registers).
H
<Target slave device area>
b0 bF
Read
<Target slave device area>
Write
b0 bF
MELSEC-Q
Access Points Setting Range
Read points Write point
1 to 2000
1 to 2000
1 to 125
1 to 125
1 to 124
1 to 1968
1 to 123
1 to 122
1 to 125 1 to 121
to
b0
116640 to 116625
116656 to 116641
116672 to 116657
to
b0
122544 to 122529
10 - 5