MPU6050陀螺仪和加速度计的校准

加速度计和陀螺仪的校准：

在传感器静止不动水平放置时，测出陀螺仪和加速度计各轴的偏移值，保存。以后每次上电调用dmp_set_xx_bias()就行了。

u8 run_self_test(void)
{
	int result;
	//char test_packet[4] = {0};
	long gyro[3], accel[3];
	result = mpu_run_self_test(gyro, accel);
	if (result == 0x3)
	{
		/* Test passed. We can trust the gyro data here, so let's push it down
		* to the DMP.
		*/
		float sens;
		unsigned short accel_sens;
		mpu_get_gyro_sens(&sens);
		gyro[0] = (long)(gyro[0] * sens);
		gyro[1] = (long)(gyro[1] * sens);
		gyro[2] = (long)(gyro[2] * sens);
		dmp_set_gyro_bias(gyro);
		mpu_get_accel_sens(&accel_sens);
		accel[0] *= accel_sens;
		accel[1] *= accel_sens;
		accel[2] *= accel_sens;
		dmp_set_accel_bias(accel);
		return 0;
	}else return 1;
}