stm32 i2c mpu9250

Question

Im working on stm32f4 series microcontroller. 
 I'm trying to read mpu9250 three sensors(accelerometer,gyroscope ,magnetometer) data from fifo buffer. I'm not able to read magnetormeter data from FIFO buffer Because I may have made errors on the I2C master and slave(slave 0) configuration. I have attached the code. I require help in resolving this. 
 void mpu9250_init()
{
	HAL_StatusTypeDef ret = HAL_I2C_IsDeviceReady(&hi2c1,0x68<<1,1,100);

// REG 107 PWR_MGMT_1 wake up
	//SLEEP When set to 0, this bit puts the MPU out of sleep mode.0x6b
	uint8_t data = 0x00;
	ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1,107,1,&data,1,100);
 HAL_Delay(100);

//register 27 or 0x1b,GYRO_FS_SEL configure gyro sensitivity full scale range
	data = 0x10; // +/- 1000 degree/sec 32.8
	ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1, 27, 1,&data,1,100);
	HAL_Delay(100);

//register 28 or 0x1c,ACCEL_FS_SEL configure ACCEL_CONFIG
	data = 0x10; // +/- 8g 4,096
	ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1, 28, 1,&data,1,100);
	HAL_Delay(100);

data = 0x01; // DLPF (184HZ BW gyroscope) results in 1000hz output
	ret = HAL_I2C_Mem_Write(&hi2c1,0x68<<1,26, 1,&data,1,100);
	HAL_Delay(100);

data = 0x01; // DLPF (ACC CONFIG2 218.1 BW)
 ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1,29 , 1,&data,1,100);
 HAL_Delay(100);

data = 0x04; // sample rate divider
	ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1, 25, 1,&data,1,100);
	HAL_Delay(100);

//Magnetometer I2C Master

//uint8_t temp6_data = 0X02; // Set bypass mode for the magnetometer.(im not using this bcoz i want to do with i2c master)
//ret = HAL_I2C_Mem_Write(&hi2c1,0x68<<1,55,1,&temp6_data,1,100);
//HAL_Delay(200);

//( PWR_MGMNT_1, CLOCK_SEL_PLL )
 data = 0x01;
 ret = HAL_I2C_Mem_Write(&hi2c1, 0x68<<1,107, 1,&data,1,100);
 HAL_Delay(100);

//( USER_CTRL, I2C_MST_EN )
 //Enable I2C Master Mode
 data = 0b0010000;//(bit 5) 
 HAL_I2C_Mem_Write(&hi2c1, 0x68 << 1,106, 1, &data, 1,100);
 HAL_Delay(100);

//( I2C_MST_CTRL,I2C_MST_CLK )
 //set the I2C bus speed to 400 kHz ,set 13 = D
 data = 0x0D; // Enable I2C Master reg 36 I2C_MST_CTRL (0X24)
 HAL_I2C_Mem_Write(&hi2c1, 0x68 << 1,36, 1, &data, 1,100);
 HAL_Delay(200);

//Configure i2c slave register
 //Set SLV0 to read from AK8963
 // AK8963_ADDR; // Set I2C address of magnetometer // REG 43(0X2B) I2C_SLV0_ADDR
 data = 0x8C;//0b10001100
 ret = HAL_I2C_Mem_Write(&hi2c1, 0x68 << 1,37, 1, &data, 1,100);
 HAL_Delay(100);

//Configure the I2C Master to access magnetometer data
 data = 0X03; //Set Slave 0 to read from AK8963 //I2C_SLV0_REG
 ret = HAL_I2C_Mem_Write(&hi2c1, 0x68 << 1,38, 1, &data, 1,100);
 HAL_Delay(100);

//Set the number of bytes to read from AK8963
 data = 0x88; // 8 bytes of data from magnetometer // I2C_SLV0_CTRL 1000 1000
 ret = HAL_I2C_Mem_Write(&hi2c1, 0x68 << 1,39, 1, &data, 1,100);
 HAL_Delay(100);

//AK8963(magnetometer) init

//(AK8963_CNTL1,AK8963_PWR_DOWN)
 data = 0x00; //power down the magnetometer (CNTL1)
 ret = HAL_I2C_Mem_Write(&hi2c1,0x0C<<1,0x0A,1,&data,1,100);

// Set 16-bits output & fuse ROM access mode
 data = 0x0F;
 ret = HAL_I2C_Mem_Write(&hi2c1,0x0C<<1,0x0A,1,&data,1,100);
 //power down the magnetometer (CNTL1)
 data = 0x00;
 ret = HAL_I2C_Mem_Write(&hi2c1,0x0C<<1,0x0A,1,&data,1,100);

//reset magnetometer
 data = 0x01;// CONTROL 2 (0 NORMAL OR 1 RESET)
 ret = HAL_I2C_Mem_Write(&hi2c1,0x0C<<1,0x0B,1,&data,1,100);

// Request continuous magnetometer measurements
 data = 0x06;
 ret = HAL_I2C_Mem_Write(&hi2c1,0x0C<<1,0x0A,1,&data,1,100);

//Enable fifo for Accelerometer,Magnetometer,Gyroscope

// set fifo en (bit 6) in USER_CTRL REG (0X6A)
 data = 0b01100000;//40 fifo enable //bit 5 for i2c master enable
 ret = HAL_I2C_Mem_Write(&hi2c1,0x68<<1,106,1,&data,1,100);
 HAL_Delay(100);

data = 0b01000000;//bit 6 set to 1 (no overwrite)
 ret = HAL_I2C_Mem_Write(&hi2c1,0x68<<1,26,1,&data,1,100);
 HAL_Delay(100);

//Enable fifo for gyro and acc and mag - in REG 35 set 0b01111100 0x78
 data = 0b01111001;//
 ret = HAL_I2C_Mem_Write(&hi2c1,0x68<<1,35,1,&data,1,100);
 HAL_Delay(100);

}
//Registers 59 to 64 – Accelerometer Measurements
//Registers 0X03 to 0x08 - Magnetometer Measurements
//Registers 67 to 72 – Gyroscope Measurements

uint8_t data_acc[6]={};
uint8_t data_gyro[6]={};
uint8_t data_mag[6]={};

uint8_t fifo_count[2];
uint16_t fifo_size;
uint8_t fifo_data[23];
uint16_t length = sizeof(fifo_data);

#define MPU9250_ADD_WRITE	0x68<<1
#define MPU9250_ADD_READ	((MPU9250_ADD_WRITE)|(0x01))
void mpu9250_read()
{
	//FIFO_COUNTH 114 ,FIFO_COUNTL 115,FIFO_R_W 116
	HAL_StatusTypeDef ret1 = HAL_I2C_Mem_Read(&hi2c1,MPU9250_ADD_READ,114,1,&fifo_count[0],6,100);
	ret1 = HAL_I2C_Mem_Read(&hi2c1,MPU9250_ADD_READ,115,1,&fifo_count[1],6,100);
	fifo_size = (fifo_count[0]<<8)|fifo_count[1];

if (fifo_size < length)
	{
 length = fifo_size;
	}
	ret1 = HAL_I2C_Mem_Read(&hi2c1,0x68<<1|0x01,116,1,fifo_data,length,100);
	//return fifo_data[0];

x_acc = (uint16_t)fifo_data[0]<<8|fifo_data[1];
	y_acc = (uint16_t)fifo_data[2]<<8|fifo_data[3];
	z_acc = (uint16_t)fifo_data[4]<<8|fifo_data[5];

x_gyro = (uint16_t)fifo_data[6]<<8|fifo_data[7];
	y_gyro = (uint16_t)fifo_data[8]<<8|fifo_data[9];
	z_gyro = (uint16_t)fifo_data[10]<<8|fifo_data[11];

x_mag = (uint16_t)fifo_data[12]<<8|fifo_data[13];
	y_mag = (uint16_t)fifo_data[14]<<8|fifo_data[15];
	z_mag = (uint16_t)fifo_data[16]<<8|fifo_data[17];
}

aswinvenu · Accepted Answer

Two points here 
 1) Make sure that HAL_I2C_isDeviceReady is returning true. else you can loop it until the peripheral is ready 
 2) Looks like your HAL_I2C_Mem_Read function call is made with the wrong parameters. 
 #define MPU9250_ADD_WRITE 0x68<<1
#define MPU9250_ADD_READ ((MPU9250_ADD_WRITE)|(0x01))

HAL_StatusTypeDef ret1 = HAL_I2C_Mem_Read(&hi2c1,MPU9250_ADD_READ,114,1,&fifo_count[0],6,100); 
 You don't need to explicitly toggle the LSB for read and write. 
 
 @param DevAddress Target device address: The device 7 bits address value * in datasheet must be shifted to the left before calling the interface

stm32 i2c mpu9250

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