Mitsubishi FX3U Series User Manual page 51

FX Series Programmable Controllers
3U
User's Manual - MODBUS Serial Communication Edition
The following are calculation examples in the case where function code 01H is sent to station No. 2.
The following table illustrates the 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)
Start Address field Function code
: (02 )
H
3A 30 32 30
H H H
LRC in request message transmission
02
01
00
00
00
08
0B
F4
F5
F5
Head input number
(01 )
H
(00
H)
31 30 30 30
H H H H
0000
0000
0000
0000
0000
+0000
0000
1111
1111
F
Read points
(00 (00
H) H)
30 30 30 30
H H H H
7 MODBUS Standard Commands
7.2 Frame Specifications
0010
0001
0000
0000
0000
1000
1011
0100
1
0101
5
LRC
(Error check) "CR"
(F5 )
(08
H
H)
38 46 35 0D
H H H H
1
2
3
4
"LF"
5
0A
H H
6
7
8
9
10
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