IIC地址控制

// ADO0 为0 控制MPU9250的IIC地址为0x68
static void MPU_ADDR_CTRL(void)
{
	GPIO_InitTypeDef GPIO_InitStructure;
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
	/*设置GPIO模式为通用推挽输出*/
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
	GPIO_InitStructure.GPIO_OType=GPIO_OType_PP;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	GPIO_ResetBits(GPIOB, GPIO_Pin_14);
}

IIC引脚初始化

//初始化IIC
void MPU_IIC_Init(void)
{		
	#if ENABLE_I2C_PB10_PB11
	GPIO_InitTypeDef  GPIO_InitStructure;
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);//先使能外设IO PORTC时钟 
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10|GPIO_Pin_11;	 // 端口配置
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; 		 //推挽输出
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;		 //IO口速度为50MHz
	GPIO_Init(GPIOB, &GPIO_InitStructure);					 //根据设定参数初始化GPIO 	
	GPIO_SetBits(GPIOB,GPIO_Pin_10|GPIO_Pin_11);
	#else			     
	GPIO_InitTypeDef  GPIO_InitStructure;
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB,ENABLE);//先使能外设IO PORTC时钟 
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13|GPIO_Pin_15;	 // 端口配置
	GPIO_InitStructure.GPIO_Mode =GPIO_Mode_OUT ; 		 //推挽输出
	GPIO_InitStructure.GPIO_OType=GPIO_OType_PP;
	GPIO_InitStructure.GPIO_PuPd=GPIO_PuPd_NOPULL;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;		 //IO口速度为50MHz
	GPIO_Init(GPIOB, &GPIO_InitStructure);					 //根据设定参数初始化GPIO 	
	GPIO_SetBits(GPIOB,GPIO_Pin_13|GPIO_Pin_15);
	#endif
}

MPU初始化

static uint8_t MPU_Basic_Init(void)
{
	uint8_t res = 0;
	MPU_ADDR_CTRL();/* 设置IIC地址 */
	MPU_IIC_Init();/* IIC初始化 */
	MPU_Delay_ms(10);

	MPU_Write_Byte(MPU9250_ADDR, MPU_PWR_MGMT1_REG, 0X80); // Reset MPU9250 //复位MPU9250 /* 1-重置所有寄存器和已经配置数据，重置后此位将自动清 0 */
	MPU_Delay_ms(100);										   // Delay 100 ms //延时100ms
	MPU_Write_Byte(MPU9250_ADDR, MPU_PWR_MGMT1_REG, 0X00); // Wake mpu9250 //唤醒MPU9250

	MPU_Set_Gyro_Fsr(1);  // Gyroscope sensor              //陀螺仪传感器,±500dps=±500°/s ±32768 (gyro/32768*500)*PI/180(rad/s)=gyro/3754.9(rad/s)
	MPU_Set_Accel_Fsr(0); // Acceleration sensor           //加速度传感器,±2g=±2*9.8m/s^2 ±32768 accel/32768*19.6=accel/1671.84
	MPU_Set_Rate(50);	  // Set the sampling rate to 50Hz //设置采样率50Hz

	MPU_Write_Byte(MPU9250_ADDR, MPU_INT_EN_REG, 0X00);	   // Turn off all interrupts //关闭所有中断
	MPU_Write_Byte(MPU9250_ADDR, MPU_USER_CTRL_REG, 0X00); // The I2C main mode is off //I2C主模式关闭
	MPU_Write_Byte(MPU9250_ADDR, MPU_FIFO_EN_REG, 0X00);   // Close the FIFO //关闭FIFO
	// The INT pin is low, enabling bypass mode to read the magnetometer directly
	// INT引脚低电平有效，开启bypass模式，可以直接读取磁力计
	MPU_Write_Byte(MPU9250_ADDR, MPU_INTBP_CFG_REG, 0X82);
	// Read the ID of MPU9250 读取MPU9250的ID
	res = MPU_Read_Byte(MPU9250_ADDR, MPU_DEVICE_ID_REG);
	printf("MPU9250 RD ID=0x%02X\n", res);
	if (res == MPU9250_ID) // The device ID is correct //器件ID正确
	{
		MPU_Write_Byte(MPU9250_ADDR, MPU_PWR_MGMT1_REG, 0X01); // Set CLKSEL,PLL X axis as reference //设置CLKSEL,PLL X轴为参考
		MPU_Write_Byte(MPU9250_ADDR, MPU_PWR_MGMT2_REG, 0X00); // Acceleration and gyroscope both work //加速度与陀螺仪都工作
		MPU_Set_Rate(50);									   // Set the sampling rate to 50Hz //设置采样率为50Hz
	}
	else
		return 1;

	res = MPU_Read_Byte(AK8963_ADDR, MAG_WIA); // Read AK8963ID //读取AK8963ID
	printf("AK8963 RD ID=0x%02X\n", res);
	if (res == AK8963_ID)
	{
		MPU_Write_Byte(AK8963_ADDR, MAG_CNTL1, 0X11); // Set AK8963 to single measurement mode //设置AK8963为单次测量模式
	}
	else
		return 1;
	MPU_Delay_ms(30);
	return 0;
}