Default parameters for protocol delivery:
L Communication interface: RS485/RS232.
Communication format: 1 start bit, 8 data bits, no check, 1 stop bit.
Baud Rate: 9600 (Software Changeable).
Address: 1 (can be changed by software).
L Communication mode: One-to-one (or one-to-many) master-slave inquiry mode is adopted between the monitoring host and the device.
L Data Protocol: MODBUS-RTU
L Pressure Sensor Accuracy: +0.12 hPa
L Gas Pressure Sensor Range: 300-1100hPa
L Temperature and Humidity Sensor Accuracy: +1%
L Temperature Sensor Range: - 40 - 80 C
L Humidity Sensor Range: 0%-100%
MODBUS protocol commands, detailed explanations, examples
Note: Without special explanation, the data in all the following commands is 16-digit, and the slave address is the default 01.
L Register Address Table:
L Register Address Table:
Register address
(16bit/word)
Read write characteristics
MODBUS address
Store contents
Humidity value
read
00H-01H
Floating point number
Temperature value
read
02H-03H
Floating point number
Fahrenheit degree
read
04H-05H
Floating point number
K degree
read
06H-07H
Floating point number
Dew point temperature
read
08H-09H
Floating point number
Dew point humidity
read
0AH-0BH
Floating point number
FAST Dew Point Temperature
read
0CH-0DH
Floating point number
FAST dew point humidity
read
0EH-0FH
Floating point number
Atmospheric pressure
read
10H-11H
Floating point number
read
Note: Do not connect the power supply voltage to terminals other than the power supply, otherwise the module will be destroyed.
L Read the data code:
L Read the temperature data:
L Send: 01 03 00 00 02 C4 0B
L Return: 01 03 04 00 41 BC CB D2 represents 23.5 degrees
Wiring Definition: Red 24V + Black: GND Yellow: 485A Green: 485B
Note that do not connect the power supply voltage to terminals other than the power supply, otherwise the module will be burned down.
Setting station number (function code: 16H)
For example, the initial station number is 01, and the station number is set to 02.
Host Send: 01 16 00 00 02 C9 C8 (00 02 denotes the set station number)
Return from flight: 02 16 00 00 00 FF 087A
For example, the initial station number is 01, and the station number is set to 03.
Host Send: 01 16 00 00 00 03 08 08 (00 03 indicates the station number set)
Return from flight: 03 16 00 00 00 FF 09 AB
For example, the initial station number is 03 and the station number is 04.
Host Send: 03 16 00 00 00 04 48 28 (00 04 denotes the set station number)
Return from aircraft: 04 16 00 00 00 FF 08 1C
Data format read attention
When ordinary PLC touch screen configuration software is connected with this module, floating-point data format can be used directly.
Developers of C or high-level languages use the following functions for two int-to-float points
Union{
Int a[2],
Float B,
} myUnion,
The ints read out by MODBUS are passed into int a [0], int a [1], and float B is read out.
Specifications
Material
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