#include "i2c.h"#define I2C_SPEED 100000 // I2C总线速度，单位为Hzvoid i2c_init(void){ GPIO_InitTypeDef GPIO_InitStruct; I2C_InitTypeDef I2C_InitStruct; RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); // 使能GPIOB时钟 RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE); // 使能I2C1时钟 // 配置GPIOB6和GPIOB7为复用推挽输出 GPIO_InitStruct.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7; GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_OD; GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOB, &GPIO_InitStruct); // 配置I2C1为标准模式，时钟速度为100kHz I2C_InitStruct.I2C_Mode = I2C_Mode_I2C; I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2; I2C_InitStruct.I2C_OwnAddress1 = 0x00; I2C_InitStruct.I2C_Ack = I2C_Ack_Enable; I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; I2C_InitStruct.I2C_ClockSpeed = I2C_SPEED; I2C_Init(I2C1, &I2C_InitStruct); I2C_Cmd(I2C1, ENABLE); // 使能I2C1}void i2c_write(uint8_t addr, uint8_t *data, uint16_t len){ uint32_t timeout = 0; while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY)) { if (++timeout > 0x10000) return; } I2C_GenerateSTART(I2C1, ENABLE); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)) { if (++timeout > 0x10000) return; } I2C_Send7bitAddress(I2C1, addr << 1, I2C_Direction_Transmitter); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) { if (++timeout > 0x10000) return; } while (len--) { I2C_SendData(I2C1, *data++); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) { if (++timeout > 0x10000) return; } } I2C_GenerateSTOP(I2C1, ENABLE);}void i2c_read(uint8_t addr, uint8_t *data, uint16_t len){ uint32_t timeout = 0; while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY)) { if (++timeout > 0x10000) return; } I2C_GenerateSTART(I2C1, ENABLE); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)) { if (++timeout > 0x10000) return; } I2C_Send7bitAddress(I2C1, addr << 1, I2C_Direction_Receiver); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED)) { if (++timeout > 0x10000) return; } while (len--) { if (len == 0) I2C_AcknowledgeConfig(I2C1, DISABLE); timeout = 0; while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED)) { if (++timeout > 0x10000) return; } *data++ = I2C_ReceiveData(I2C1); } I2C_AcknowledgeConfig(I2C1, ENABLE); I2C_GenerateSTOP(I2C1, ENABLE);}

以下是使用STM32 HAL库函数实现的代码示例：

#include "stm32f1xx_hal.h"

#define I2C_SPEED 100000

I2C_HandleTypeDef hi2c1;

void i2c_init(void)
{
  hi2c1.Instance = I2C1;
  hi2c1.Init.ClockSpeed = I2C_SPEED;
  hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2;
  hi2c1.Init.OwnAddress1 = 0x00;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }
}

void i2c_write(uint8_t addr, uint8_t *data, uint16_t len)
{
  if (HAL_I2C_Master_Transmit(&hi2c1, addr << 1, data, len, HAL_MAX_DELAY) != HAL_OK)
  {
    Error_Handler();
  }
}

void i2c_read(uint8_t addr, uint8_t *data, uint16_t len)
{
  if (HAL_I2C_Master_Receive(&hi2c1, addr << 1, data, len, HAL_MAX_DELAY) != HAL_OK)
  {
    Error_Handler();
  }
}

以上代码使用STM32 HAL库函数实现了I2C初始化、写入和读取操作。请注意，需要在CubeMX工具中配置I2C时钟和GPIO引脚。