【GMT43智能液晶模块】例程十二：SDIO实验——读取SD卡信息

实验原理：

　　STM32F429上带有SDIO控制器，GMT43液晶模块上将SDIO连接到TF卡座上。本

实验将Micro SD卡插入TF卡座上即可。SD卡中可存放液晶显示模块需要显示的图片、字

库等资源。

示例截图：

源代码下载链接：

链接：https://pan.baidu.com/s/1kXf5erd 密码：8qpr

GMT43购买链接：

核心代码：

SD_Error SD_Init(void)
{
  __IO SD_Error errorstatus = SD_OK;
    
    NVIC_InitTypeDef NVIC_InitStructure;
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
    // SDIO Interrupt ENABLE
    NVIC_InitStructure.NVIC_IRQChannel = SDIO_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    // DMA2 STREAMx Interrupt ENABLE
    NVIC_InitStructure.NVIC_IRQChannel = SD_SDIO_DMA_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_Init(&NVIC_InitStructure);
  
  /* SDIO Peripheral Low Level Init */
  SD_LowLevel_Init();

  SDIO_DeInit();

  errorstatus = SD_PowerON();

  if (errorstatus != SD_OK)
  {
    /*!< CMD Response TimeOut (wait for CMDSENT flag) */
    return(errorstatus);
  }

  errorstatus = SD_InitializeCards();

  if (errorstatus != SD_OK)
  {
    /*!< CMD Response TimeOut (wait for CMDSENT flag) */
    return(errorstatus);
  }

  /*!< Configure the SDIO peripheral */
  /*!< SDIO_CK = SDIOCLK / (SDIO_TRANSFER_CLK_DIV + 2) */
  /*!< on STM32F4xx devices, SDIOCLK is fixed to 48MHz */
  SDIO_InitStructure.SDIO_ClockDiv = SDIO_TRANSFER_CLK_DIV;
  SDIO_InitStructure.SDIO_ClockEdge = SDIO_ClockEdge_Rising;
  SDIO_InitStructure.SDIO_ClockBypass = SDIO_ClockBypass_Disable;
  SDIO_InitStructure.SDIO_ClockPowerSave = SDIO_ClockPowerSave_Disable;
  SDIO_InitStructure.SDIO_BusWide = SDIO_BusWide_1b;
  SDIO_InitStructure.SDIO_HardwareFlowControl = SDIO_HardwareFlowControl_Disable;
  SDIO_Init(&SDIO_InitStructure);

  /*----------------- Read CSD/CID MSD registers ------------------*/
  errorstatus = SD_GetCardInfo(&SDCardInfo);

  if (errorstatus == SD_OK)
  {
    /*----------------- Select Card --------------------------------*/
    errorstatus = SD_SelectDeselect((uint32_t) (SDCardInfo.RCA << 16));
  }

  if (errorstatus == SD_OK)
  {
    errorstatus = SD_EnableWideBusOperation(SDIO_BusWide_4b);
  }  

  return(errorstatus);
}