HMC5883L 3축 자계 모듈 테스트
1. HMC5883L
쿼드콥터 만들 때 MPU-6050 센서와 함께 사용하면 자세저어가 가능합니다. MPU-6050 에서 Z축 회전(Yawing, 정지상태에서 좌우회전 움직임)을 정확히 잡을 수 없으므로 HMC5883L 을 사용해서 보완할 수 있습니다.
2. 연결방법
- Arduino GND -> HMC5883L GND
- Arduino 3.3V -> HMC5883L VCC
- Arduino A4 (SDA) -> HMC5883L SDA
- Arduino A5 (SCL) -> HMC5883L SCL
- You will also need to add two ‘pull-up’ resistors to enable I2C. For this, connect two 4.7k or 10k resistors between SDA and VCC, and SCL and VCC. (이 부분은 필요 없는듯)
3. 소스코드
3-1. 단순한 형태의 Raw 데이터 읽기/출력
http://sfecdn.s3.amazonaws.com/datasheets/Sensors/Magneto/HMC5883.pde
/* An Arduino code example for interfacing with the HMC5883 by: Jordan McConnell SparkFun Electronics created on: 6/30/11 license: OSHW 1.0, http://freedomdefined.org/OSHW Analog input 4 I2C SDA Analog input 5 I2C SCL */ #include <Wire.h> //I2C Arduino Library #define address 0x1E //0011110b, I2C 7bit address of HMC5883 void setup(){ //Initialize Serial and I2C communications Serial.begin(9600); Wire.begin(); //Put the HMC5883 IC into the correct operating mode Wire.beginTransmission(address); //open communication with HMC5883 Wire.send(0x02); //select mode register Wire.send(0x00); //continuous measurement mode Wire.endTransmission(); } void loop(){ int x,y,z; //triple axis data //Tell the HMC5883 where to begin reading data Wire.beginTransmission(address); Wire.send(0x03); //select register 3, X MSB register Wire.endTransmission(); //Read data from each axis, 2 registers per axis Wire.requestFrom(address, 6); if(6<=Wire.available()){ x = Wire.receive()<<8; //X msb x |= Wire.receive(); //X lsb z = Wire.receive()<<8; //Z msb z |= Wire.receive(); //Z lsb y = Wire.receive()<<8; //Y msb y |= Wire.receive(); //Y lsb } //Print out values of each axis Serial.print("x: "); Serial.print(x); Serial.print(" y: "); Serial.print(y); Serial.print(" z: "); Serial.println(z); delay(250); }
3-2. HMC5883L 라이브러리 사용해서 작성하는 방법
http://bildr.org/2012/02/hmc5883l_arduino/
4. 동작방법
(작성중)
5. 참고자료
HMC5883L Compass tutorial with Arduino library : http://www.loveelectronics.co.uk/Tutorials/8/hmc5883l-tutorial-and-arduino-library
HMC5883L How to : http://bildr.org/2012/02/hmc5883l_arduino/
Digital compass How-to video