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STM32F4Discovery i2c using

Question asked by ogan.s.alper on Jan 22, 2013
I need to use I2C1 ports for communication with LG3D20(0xD6 adress) gyro sensor.Accordingly, i need i2c1 initial,i2c1 write data 1 byte,i2c1 read data 1 byte functions.I am using these functions but i couldnt run this function in program flow.The program always lockups at I2C_GetFlagStatus(I2C2, I2C_FLAG_BUSY).Please give me an tried example for stm32f4discovery i2c1.My codes are here:

     /*  I2C1  */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
  GPIO_PinAFConfig(GPIOB,GPIO_PinSource6, GPIO_AF_I2C1);
  GPIO_PinAFConfig(GPIOB,GPIO_PinSource7, GPIO_AF_I2C1);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
  GPIO_Init(GPIOB, &GPIO_InitStructure);



I2C_DeInit(I2C1);
     
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
    I2C_init.I2C_Mode = I2C_Mode_I2C;
    I2C_init.I2C_ClockSpeed = 100000;
    I2C_init.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_init.I2C_OwnAddress1 = 0;
    I2C_init.I2C_Ack = I2C_Ack_Enable;
    I2C_init.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
       I2C_Cmd(I2C1,ENABLE);
    I2C_Init(I2C1,&I2C_init);

   unsigned short int I2C1_read(uint8_t adress, uint8_t index)
   { 
   uint8_t data;
   while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
    I2C_GenerateSTART(I2C1, ENABLE);
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
    I2C_Send7bitAddress(I2C1, adress, I2C_Direction_Transmitter);
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
    I2C_SendData(I2C1, index);
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
    I2C_GenerateSTART(I2C1, ENABLE);
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
    I2C_Send7bitAddress(I2C1, adress, I2C_Direction_Receiver);
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
    data=I2C_ReceiveData(I2C1);
    I2C_GenerateSTOP(I2C1, ENABLE);
          return data;
   }

      void I2C1_write(uint8_t adress, uint8_t * data) {
    uint8_t i=0;
    while (i < 7) 
          {
        while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
        I2C_GenerateSTART(I2C1, ENABLE);
        while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
        I2C_Send7bitAddress(I2C1, adress, I2C_Direction_Transmitter);
        while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
        I2C_SendData(I2C1, data[i]);
        while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
        I2C_SendData(I2C1,i + 1);
        while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
        I2C_GenerateSTOP(I2C2, ENABLE);
        i+=2;
    }
      }

int main(void)
{
     uint8_t timer_value,flag=0,i=0;
     char buffer[8];
     uint8_t deger;
     
     I2C1_Initialize();
  while (1)
  {
          deger=I2C2_read(0x3C,0x20);
          sprintf(buffer,"%d",deger);
          USART3_Write_Text(buffer);
          USART3_Write_Text("\n\r");
     }
}

I need read,write,initial functions for stm32f4discovery kit's I2C1!!!

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