stm32驱动AD7685进行电压采集的程序

以下是使用STM32驱动AD7685进行电压采集的程序，仅供参考：

1. 配置SPI接口

SPI_HandleTypeDef hspi1;

void MX_SPI1_Init(void)
{
  /* SPI1 parameter configuration*/
  hspi1.Instance = SPI1;
  hspi1.Init.Mode = SPI_MODE_MASTER;
  hspi1.Init.Direction = SPI_DIRECTION_2LINES;
  hspi1.Init.DataSize = SPI_DATASIZE_16BIT;
  hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
  hspi1.Init.NSS = SPI_NSS_SOFT;
  hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_32;
  hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi1.Init.CRCPolynomial = 10;
  if (HAL_SPI_Init(&hspi1) != HAL_OK)
  {
    Error_Handler();
  }
}

2. 定义AD7685相关寄存器地址

#define AD7685_CONVERSION_REG 0x8000
#define AD7685_SETUP_REG 0x2000
#define AD7685_STATUS_REG 0x0000
#define AD7685_CONFIG_REG 0x4000

3. 配置AD7685

void AD7685_Init(void)
{
  uint16_t txBuf[2];
  // 设置采样率为500kSPS
  txBuf[0] = AD7685_SETUP_REG | 0x0C00;
  HAL_SPI_Transmit(&hspi1, txBuf, 1, 100);
  HAL_Delay(1);
  // 配置转换模式为单端输入
  txBuf[0] = AD7685_CONFIG_REG | 0x0000;
  HAL_SPI_Transmit(&hspi1, txBuf, 1, 100);
  HAL_Delay(1);
}

4. 读取AD7685采样数据

uint16_t AD7685_Read(void)
{
  uint16_t txBuf[2], rxBuf[2];
  // 发送转换命令
  txBuf[0] = AD7685_CONVERSION_REG | 0x0000;
  HAL_SPI_Transmit(&hspi1, txBuf, 1, 100);
  // 读取采样数据
  HAL_SPI_Receive(&hspi1, rxBuf, 1, 100);
  return rxBuf[0];
}

5. 采集电压并转换成实际电压值

#define V_REF 3.3 // 参考电压
#define V_GAIN 2 // 增益

float AD7685_GetVoltage(void)
{
  uint16_t adcData = AD7685_Read();
  float voltage = adcData * V_REF / (V_GAIN * pow(2, 16));
  return voltage;
}

注意：以上代码仅供参考，实际使用时需要根据具体情况进行修改。