RS485 Wind Vane Direction Sensor - Example Code for Arduino-Wind Direction Reading

This article provides example code for reading wind direction using Arduino and RS485 transmitter. It includes detailed hardware and software setup, wiring diagrams, and sample code to help users accurately read wind angle from 0 to 360 degrees.

Hardware Preparation

Name	Model/SKU	Quantity	Purchase Link
RS485 Wind Direction Transmitter	SEN0482	1	DFRobot Product Page
Gravity: Active Isolated RS485 to UART Signal Adapter Module	DFR0844	1	DFRobot Product Page
Arduino Uno	DFR0009	1	DFRobot Product Page

Software Preparation

Arduino IDE (compatible with all modern versions)
Download and install the RS485_Wind_Direction_Transmitter_V2 Library. Refer to How to install the library? for step-by-step instructions.

Wiring Diagram

Sample Code

#include "RS485_Wind_Direction_Transmitter_V2.h"


/**Arduino
   @brief RS485_Wind_Direction_Transmitter_V2 constructor
   @param serial - serial ports for communication, supporting hard and soft serial ports
   @param rx - UART the pin for receiving data
   @param tx - UART the pin for transmitting data
*/
#if defined(ARDUINO_AVR_UNO)||defined(ESP8266)   // use soft serial port
SoftwareSerial softSerial(/*rx =*/2, /*tx =*/3);
RS485_Wind_Direction_Transmitter_V2 windDirection(/*softSerial =*/&softSerial);
#elif defined(ESP32)   // use the hard serial port with remapping pin : Serial1
RS485_Wind_Direction_Transmitter_V2 windDirection(/*hardSerial =*/&Serial1, /*rx =*/D3, /*tx =*/D2);
#else   // use the hard serial port : Serial1
RS485_Wind_Direction_Transmitter_V2 windDirection(/*hardSerial =*/&Serial1);
#endif

uint8_t Address = 0x02;

const char* Orientation[17] = {
  "North", "North-northeast", "Northeast", "East-northeast", "East", "East-southeast", "Southeast", "South-southeast", "South",
  "South-southwest", "Southwest", "West-southwest", "West", "West-northwest", "Northwest", "North-northwest", "North"
};

void setup()
{
  Serial.begin(115200);

  // Init the sensor
  while ( !( windDirection.begin() ) ) {
    Serial.println("Communication with device failed, please check connection");
    delay(3000);
  }
  Serial.println("Begin ok!");
//Change modbus slave address, and you can use 0x00 broadcast address to change it if you forgot the current address.
//  windDirection.SetSlaveAddress(/*the current modbus slave address*/0x00, /*the address after the change*/0x02);
//Get modbus slave address
//  Address = windDirection.GetSlaveAddress();
}

void loop()
{
  //Get 16 wind directions
  int Direction = windDirection.GetWindDirection(/*modbus slave address*/Address);
  //Get 360° wind direction
  float Angle = windDirection.GetWindAngle(/*modbus slave address*/Address);
  Serial.println(Orientation[Direction]);
  Serial.print(Angle); Serial.println("°");
  Serial.println();
  delay(1000);
}

Result

The development board will acquire the wind direction and wind angle (0-360°) from the sensor.