2018年06月03日 | STM32L系列+ADXL345的I2C调试

STM32的硬件I2C调试确实要比模拟麻烦很多啊，一大堆的配置，调通F系列的，本以为直接移植到L系列会很轻松，没想到问题依然很多，现直接附上STM32L系列的I2C初始化及读写函数：

1.GPIO的初始化：

static void ADXL_LowLevel_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;

/* 使能与 I2C1 有关的时钟 */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB,ENABLE); 
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1,ENABLE);  


GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOB, &GPIO_InitStructure); 


  /*!< Configure sEE_I2C pins: SDA */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
/* Connect PXx to I2C_SCL*/
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1);


/* Connect PXx to I2C_SDA*/
GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_I2C1);
  
}

2.I2C的初始化：

void I2C_ADXL_Init(void)
{  
I2C_InitTypeDef I2C_InitStructure;
ADXL_LowLevel_Init(); 
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
  I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
  I2C_InitStructure.I2C_OwnAddress1 = ADXL_ADRESS;
  I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
  I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  I2C_InitStructure.I2C_ClockSpeed = I2C_Speed;
  
  /* ADXL_I2C Peripheral Enable */
  I2C_Cmd(I2C1, ENABLE);
  /* Apply MEMS_I2C configuration after enabling it */
  I2C_Init(I2C1, &I2C_InitStructure); 
}

3.读

u8 I2C_ADXL_ByteRead(u8 ReadAddr)
{
u8 RxData;
/*wait until I2C bus is not busy*/
  while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
/* Send START condition */
  I2C_GenerateSTART(I2C1, ENABLE);
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
  /* Send ADXL address for write */
  I2C_Send7bitAddress(I2C1, ADXL_ADRESS, I2C_Direction_Transmitter);
    /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
    /* Send the ADXL's Register address to write to */
  I2C_SendData(I2C1, ReadAddr);  
    while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BTF) == RESET);
  /* Send STRAT condition a second time */  
  I2C_GenerateSTART(I2C1, ENABLE);
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
  /* Send ADXL address for read */
  I2C_Send7bitAddress(I2C1, ADXL_ADRESS, I2C_Direction_Receiver);
  while(I2C_GetFlagStatus(I2C1, I2C_FLAG_ADDR) == RESET);
  /* Disable Acknowledgement */
    I2C_AcknowledgeConfig(I2C1, DISABLE);
(void)I2C1->SR2;
  
  /*!< Send STOP Condition */
  I2C_GenerateSTOP(I2C1, ENABLE);
  while(I2C_GetFlagStatus(I2C1, I2C_FLAG_RXNE) == RESET);
  
/* Read a byte from the ADXL Register */
RxData = I2C_ReceiveData(I2C1);
while(I2C1->CR1 & I2C_CR1_STOP);
    I2C_AcknowledgeConfig(I2C1, ENABLE);


return RxData;
}

4. 写

void I2C_ADXL_ByteWrite(u8 pBuffer, u8 WriteAddr)
{
  /*wait until I2C bus is not busy*/
  while(I2C_GetFlagStatus(I2C1,I2C_FLAG_BUSY));
    
/* Send START condition */
  I2C_GenerateSTART(I2C1, ENABLE);
  
    /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)); 
  
   /* Send MMA address for write */
  I2C_Send7bitAddress(I2C1, ADXL_ADRESS, I2C_Direction_Transmitter);
    
/* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
   
    /* Send the MMA's Register address to write to */    
  I2C_SendData(I2C1, WriteAddr); 
  
  /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
   
    /* Send the byte to be written */
  I2C_SendData(I2C1, pBuffer);
  
   /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));  
   
   /* Send STOP condition */
  I2C_GenerateSTOP(I2C1, ENABLE);


}