README.md

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;

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

    Wire.begin();

    delay(2000);
    mpu.setup();
}

void loop()
{
    static uint32_t prev_ms = millis();
    if ((millis() - prev_ms) > 16)
    {
        mpu.update();
        mpu.print();

        Serial.print("roll  (x-forward (north)) : ");
        Serial.println(mpu.getRoll());
        Serial.print("pitch (y-right (east))    : ");
        Serial.println(mpu.getPitch());
        Serial.print("yaw   (z-down (down))     : ");
        Serial.println(mpu.getYaw());

        prev_ms = millis();
    }
}

Calibration

• device should be stay still during accel/gyro calibration
• round device around during mag calibration

#include "MPU9250.h"

MPU9250 mpu;

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

    Wire.begin();

    delay(2000);
    mpu.setup();

    delay(5000);

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

    mpu.printCalibration();
}

void loop()
{
}

Other Settings

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 }; // 0.6mG, 0.15mG per LSB

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

License

MIT

Acknowledgments / Contributor

• Yuta Asai