stm32f407 i2c2初始化及数据发送代码

以下是STM32F407的I2C2初始化和数据发送代码：

#include "stm32f4xx.h"

void I2C2_Init(void)
{
  GPIO_InitTypeDef  GPIO_InitStructure;
  I2C_InitTypeDef   I2C_InitStructure;

  /* Enable GPIOB clock */
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

  /* Enable I2C2 clock */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);

  /* Configure I2C2 pins: SCL and SDA */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
  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_UP;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  /* Connect pins to I2C2 */
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_I2C2);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_I2C2);

  /* Configure I2C2 */
  I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
  I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
  I2C_InitStructure.I2C_OwnAddress1 = 0x00;
  I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
  I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  I2C_InitStructure.I2C_ClockSpeed = 100000; // 100 kHz

  /* Initialize I2C2 */
  I2C_Init(I2C2, &I2C_InitStructure);

  /* Enable I2C2 */
  I2C_Cmd(I2C2, ENABLE);
}

void I2C2_SendData(uint8_t addr, uint8_t *data, uint8_t len)
{
  uint8_t i;

  /* Wait for I2C2 to be ready */
  while (I2C_GetFlagStatus(I2C2, I2C_FLAG_BUSY));

  /* Generate start condition */
  I2C_GenerateSTART(I2C2, ENABLE);

  /* Wait for start condition to be generated */
  while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));

  /* Send address of slave device */
  I2C_Send7bitAddress(I2C2, addr, I2C_Direction_Transmitter);

  /* Wait for address to be sent */
  while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));

  /* Send data */
  for (i = 0; i < len; i++)
  {
    /* Send data */
    I2C_SendData(I2C2, data[i]);

    /* Wait for data to be sent */
    while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  }

  /* Generate stop condition */
  I2C_GenerateSTOP(I2C2, ENABLE);
}

这段代码中，`I2C2_Init()`函数用于初始化I2C2总线，`I2C2_SendData()`函数用于向I2C2设备发送数据。需要注意的是，在使用`I2C2_SendData()`函数发送数据前，需要先调用`I2C2_Init()`函数对I2C2总线进行初始化。此外，还需要根据实际情况修改代码中的设备地址和数据长度等参数。