SONBEST SM1635B2, User Manual

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SM1635B2 Us er Ma nual
http://www.sonbus.com/
Sha nghai Son
best Industrial Co., Ltd Page2
Brand SONBEST
Communication Interface RS485
Default baud rate 9600 8 n 1
Power DC9~24V 1A
Wiring instructions
Any incorrect wiring can cause irreversible damage to the product. Please carefully wire the cable as
follows in the case of power failure, and then connect the cable to confirm the correctness and then use it
again.
ID Core color Identification Note
1 Red V+ Power +
2 Green V- Power -
3 Yellow A+ RS485 A+
4 Blue B- RS485 B-
In the case of broken wires, wire the wires as shown in the figure. If the product itself has no leads, the
core color is for reference.
Communication Protocol
The product uses RS485 MODBUS-RTU standard protocol format, all operation or reply commands
are hexadecimal data. The default device address is 1 when the device is shipped, the default baud rate is
9600, 8, n, 1
1. Read Data (Function id 0x03)
Inquiry frame (hexadecimal), sending example: Query 1# device 1 data, the host computer sends the
command:01 03 00 00 00 01 84 0A .
Device ID Function id Start Address Data Length CRC16
01 03 00 00 00 01 84 0A
For the correct query frame, the device will respond with data:01 03 02 00 79 79 A6 , the response
format is parsed as follows:
Device ID Function id Data Length
数据
1 Check Code
01 03 02 00 79 79 A6
Data Description: The data in the command is hexadecimal. Take data 1 as an example. 00 79 is
converted to a decimal value of 121. If the data magnification is 100, the actual value is 121/100=1.21.
Others and so on.
2. Data Address Table
Address Start Address Description Data type Value range
40001 00 00 1#4-20MAcurrentregister Read only 0~65535
40101 00 64 model code read/write 0~65535
40102 00 65 total points read/write 1~20
40103 00 66 Device ID read/write 1~249
40104 00 67 baud rate read/write 0~6
40105 00 68 mode read/write 1~4
40106 00 69 protocol read/write 1~10
3 read and modify device address
(1) Read or query device address
If you don't know the current device address and there is only one device on the bus, you can use the