SLAVE_ADD:1 ->MODBU Slave address 1
Parameters:
Product name: temperature and humidity transmitter
DC power supply: DC 5V-30V
Output signal: RS485 signal
Temperature accuracy: ±0.5¡É (25¡É)
Humidity accuracy: ±3%RH
Temperature range: 0%RH-80%RJ
Temperature resolution: 0.1¡É
Humidity resolution: 0.1%RH
Power consumption: ¡Â0.2W
Communication address: 1-247 can be set, default 1
Communication protocol: Modbus-RTU protocol and custom common protocol
Baud rate: configurable, default 9600, 8-bit data, 1-bit stop, no parity
Wiring:
Modbus protocol:
0x03:Read keep register
0x04: Read input register
0x06:Write a single keep register
0x10:Write more keep registers
Modbus Frame format:
Master send format:
The responseformat of slave:
MODBUSCOMMAND
Master read temperature command frame(0x04):
The response data from slave:
Temperature value=0x131,converted to a decimal 305,the actual temperature value = 305 / 10 = 30.5°
Note: the temperature is signed hexadecimal number, temperature value = 0xFF33, converted to a decimal - 205, the actual temperature = -20.5 °;
Master read humidity command frame(0x04)
The response data from slave:
Humidity value = 0x222, converted to a decimal 546, actual humidity value = 546/10 = 54.6 %;
Continuous read temperature and humidity command frame(0x04):
The response data from slave:
Read keep register(0x03):
Readdevice address from the slave:
The response data from slave:
Modify the contents of the registers(0x06):
Modify the slave address register:
Modify the slave address:0x08 = 8
The response data from slave(And send the same):
Continuously change keep registers(0x10):
Slave address :0x20 = 32
Baud rate :0x2580 = 9600
The response data from slave:
General Protocal
The default baud rates9600 (the user can set), 8 bits of data, one stop, no check
RS485
PARAM CMD:
TC:0.0,HC:0.0,BR:9600,HZ:1 ->Temp calibration 0.0, Humi calibration0.0, Baud rate 9600,report rate 1Hz
SLAVE_ADD:1 ->MODBU Slave address 1