README.md 4.7 KB

MPU9250

Arduino library for MPU9250 Nine-Axis (Gyro + Accelerometer + Compass) MEMS MotionTracking™ Device

This library is based on the great work by kriswiner, and re-writen for the simple usage.

Usage

Simple Measurement

#include "MPU9250.h"

MPU9250 mpu;
// MPU9255 mpu; // You can also use MPU9255

void setup() {
    Serial.begin(115200);
    Wire.begin();
    delay(2000);

    mpu.setup(0x68);  // change to your own address
}

void loop() {
    if (mpu.update()) {
        mpu.printRollPitchYaw();
    }
}

Calibration

  • device should be stay still during accel/gyro calibration
  • round device around during mag calibration
#include "MPU9250.h"

MPU9250 mpu;
// MPU9255 mpu; // You can also use MPU9255

void setup() {
    Serial.begin(115200);
    Wire.begin();
    delay(2000);

    mpu.setup(0x68);  // change to your own address

    delay(5000);

    // calibrate anytime you want to
    mpu.calibrateAccelGyro();
    mpu.calibrateMag();

    mpu.printCalibration();
}

void loop() { }

Other Settings

I2C Address

You must set your own address based on A0, A1, A2 setting as:

mpu.setup(0x70);

Other I2C library

You can use other I2C library e.g. SoftWire.

MPU9250_<SoftWire, MPU9250_WHOAMI_DEFAULT_VALUE> mpu;
SoftWire sw(SDA, SCL);

// in setup()
mpu.setup(0x70, sw);

Magnetic Declination

Magnetic declination should be set depending on where you are to get accurate data. To set it, use this method.

mpu.setMagneticDeclination(value);

You can find magnetic declination in your city here.

For more details, see wiki.

AFS, FGS, MFS

AFS

enum class AFS { A2G, A4G, A8G, A16G };

GFS

enum class GFS { G250DPS, G500DPS, G1000DPS, G2000DPS };

MFS

`enum class MFS { M14BITS, M16BITS };

How to change

MPU9250 class is defined as follows.

template <
	typename WireType,
	AFS AFSSEL = AFS::A16G,
	GFS GFSSEL = GFS::G2000DPS,
	MFS MFSSEL = MFS::M16BITS
>
class MPU9250_;

So, please use like

class MPU9250_<TwoWire, AFS::A4G, GFS::G500DPS, MFS::M14BITS> mpu; // most of Arduino
class MPU9250_<i2c_t3, AFS::A4G, GFS::G500DPS, MFS::M14BITS> mpu; // Teensy

MPU9255

To use MPU9255 instead of MPU9250, just declare MPU9255.

MPU9255 mpu;

APIs

bool setup(const uint8_t addr, WireType& w = Wire);
void verbose(const bool b);
void calibrateAccelGyro();
void calibrateMag();
bool isConnectedMPU9250();
bool isConnectedAK8963();
bool available();
bool update();

float getRoll() const;
float getPitch() const;
float getYaw() const;

float getQuaternion(uint8_t i) const;

float getQuaternionX() const;
float getQuaternionY() const;
float getQuaternionZ() const;
float getQuaternionW() const;

float getAcc(const uint8_t i) const;
float getGyro(const uint8_t i) const;
float getMag(const uint8_t i) const;

float getAccX() const;
float getAccY() const;
float getAccZ() const;
float getGyroX() const;
float getGyroY() const;
float getGyroZ() const;
float getMagX() const;
float getMagY() const;
float getMagZ() const;

float getAccBias(const uint8_t i) const;
float getGyroBias(const uint8_t i) const;
float getMagBias(const uint8_t i) const;
float getMagScale(const uint8_t i) const;

float getAccBiasX() const;
float getAccBiasY() const;
float getAccBiasZ() const;
float getGyroBiasX() const;
float getGyroBiasY() const;
float getGyroBiasZ() const;
float getMagBiasX() const;
float getMagBiasY() const;
float getMagBiasZ() const;
float getMagScaleX() const;
float getMagScaleY() const;
float getMagScaleZ() const;

float getTemperature() const;

void setAccBias(const uint8_t i, const float v);
void setGyroBias(const uint8_t i, const float v);
void setMagBias(const uint8_t i, const float v);
void setMagScale(const uint8_t i, const float v);

void setAccBiasX(const float v);
void setAccBiasY(const float v);
void setAccBiasZ(const float v);
void setGyroBiasX(const float v);
void setGyroBiasY(const float v);
void setGyroBiasZ(const float v);
void setMagBiasX(const float v);
void setMagBiasY(const float v);
void setMagBiasZ(const float v);
void setMagScaleX(const float v);
void setMagScaleY(const float v);
void setMagScaleZ(const float v);

void setMagneticDeclination(const float d);

void print() const;
void printRawData() const;
void printRollPitchYaw() const;
void printCalibration() const;

License

MIT

Acknowledgments / Contributor