SMC Networks HECR Series

MODBUS communication function
HECR 5-6
The communication example is expressed in hexadecimal value with
[ ]. The actual communication is performed in ASCII code. Refer to the
request / response message in this section.
5.5.2 Message example
The example shows communication with the conditions below.
1) Slave Address (=Unit number)：No.1
2) Read a data from register 0040H.
(Read Internal sensor temperature.)
◼ Communication example
Request message
Response message
Code
Contents
Code
Contents
01
Slave Address
01
Slave Address
03
Function
03
Function
0040
Head address of specified register
02
Quantity of bytes to read
0001
Quantity of register to read
094D
Information of 0040H
(circulating fluid discharge temperature: 23.81
o
C)
BB
LRC
A4
LRC
◼ Request message (Master to Slave)
Start
Slave Address
Function
Data
LRC
End
3A
30
31
30
33
42
42
0D
0A
Read Address
Quantity to Read
Hi
Lo
Hi
Lo
30
30
34
30
30
30
30
31
◼ Response message (Slave to Master)
Start
Slave Address
Function
Data
LRC
End
3A
30
31
30
33
41
34
0D
0A
Byte Count
Read Data1
Hi
Lo
30
32
30
39
34
4D
This product
(Request): 010300400001BB [CR][LF]
(Response): 010302094DA4 [CR][LF]
Your system
Data is sent and
received in ASCII
code.