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WPMZ Series Modbus communication instruction manual
IM-0862-02
Number of pages:109
12
2.
Function code 04H (Read input register [Read only address])
Read the measurement value of the specified read-only address.
Transmission and reception format
◎Transmission data (master
→
slave (module))
Table 3.7 Function code 04H Transmission format
n a me
Tra n smi tte d da ta
S l a v e ID
0 1 ~ F F H
Fu n c ti on c o de
0 4 H
A d d r e s s
U p p e r
0 0 0 0 ~ 2 7 0 F H
Lo w e r
N u m b e r o f w o r d s t o b e
r e a d ( D a t a l e n g t h ÷ 2 )
U p p e r
0 0 0 1 ~ 0 0 7 D H
Lo w e r
E r r o r c h e c k
( C R C - 1 6 )
Lo w e r
0 0 0 0 ~ F F F F H
U p p e r
※Specify the number of read words in units of data length for each address.
◎Received data (slave (module)
→
master)
Table 3.8 Function code 04H Reception format
n a me
Re c e i v e d d ata
S l a v e ID
0 1 ~ F F H
Fu n c ti on c o de
0 4 H
N u m b e r o f b y t e s r e a d
2 × n u m b e r o f r e a d w o r d s
F i r s t w o r d d a t a
U p p e r
0 0 0 0 ~ F F F F H
Lo w e r
N e x t w o r d d a t a
U p p e r
0 0 0 0 ~ F F F F H
Lo w e r
~
~
~
T h e l a s t w o r d d a t a
U p p e r
0 0 0 0 ~ F F F F H
Lo w e r
E r r o r c h e c k
( C R C - 1 6 )
Lo w e r
0 0 0 0 ~ F F F F H
U p p e r