2. Modbus
2.1. Configuration of parameters
• Communication speed: between 2400 and 115200 bauds, 19200 bauds by default
• Data bits: 8 bits
• Stop bit: 1 bit
• Parity: None
• Flow control: None
• Transmitter addressing: between 1 and 255 (automatically answers the requests from address 0)
• Data sending: made by words of 2 bytes, in the following order: most-significant then least-significant byte
2.2. Functions
• Register function: Function 03
• Register writing: Function 16
• Communication loop test: Function 08
2.3. Access code to register
• Registers type:
Type Size Description Format
U8 1 byte Unsigned integer 8 bits Byte 1
Example with a value of 24 (0x18) 0x18
Type Size Description Format
U16 2 bytes Unsigned integer 16
bits
Byte 2 Byte 1
Example with a value of 300 (0x012C) 0x01 0x2C
Type Size Description Format
U32 4 bytes Unsigned integer 32
bits
Byte 2 Byte 1 Byte 4 Byte 3
Example with a value of 1 096 861 217 (0x4160C621) 0xC6 0x21 0x41 0x60
Type Size Description Format
Real 4 bytes Real 32 bits Byte 2 Byte 1 Byte 4 Byte 3
Example with a value of 153.5 (0x43198000) 0x80 0x00 0x43 0x19
Type Size Description Format
Enumeration 1 byte See Enumeration table
page 8
Same as U8
Boolean 1 byte True = 1 ; False = 0 Same as U8
6 Modbus
To Next Page
Loading...
Need help?
General
