Mitsubishi Electric QJ71MB91 User Manual page 69

4
MODBUS STANDARD FUNCTIONS
Start Address field Function code
: (02 ) (01
H H
3A 30 32 30
H H H H
(2) Frame mode setting
The frame mode is set in the intelligent function module switch setting.
(
The following are calculation examples in the case where function code 01
sent to station No. 2.
Table4.6 LRC calculation procedure (when sending a request message)
Station No. (address field)
Function code
Head coil number (H)
Head coil number(L)
Read points (H)
Read points (L)
Addition result
Bit reversal 1
+1
2's complement
LRC (Error check)
Table4.7 LRC calculation procedure (when receiving a response message)
LRC in reception of a response message
Station No. (address field)
Function code
Head coil number(H)
Head coil number(L)
Read points (H)
Read points (L)
LRC (Error check)
Addition result
Head input number
)
(00 ) (00
H H
31 30 30 30
H H H H
Figure 4.5 Frame for LRC calculation
Section 6.6)
LRC in request message transmission
02
01
00
00
00
08
0B
F4
F5
F5
02
01
00
00
00
08
F5
00
Read points
) (00 ) (08
H H
30 30 30 30
H H H H
4.2 Frame Specifications
4.2.1 Frame mode
H
0000
0000
0000
0000
0000
+0000
0000
1111
1111
F 5
0000 0010
0000 0001
0000 0000
0000 0000
0000 0000
0000 1000
+1111 0101
0000 0000
LRC
(Error check) "CR"
(F5 )
)
H
38 46 35 0D
H H H H
4
1
is
0010
2
0001
0000
0000
0000
1000
1011
0100
3
1
0101
4
5
"LF"
6
0A
H
7
8
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