2019年04月25日 | STM8S105K4 SPI相关代码

/* 初始化函数 */

void SPI_FLASH_Init(void)

{

   SPI_Init(SPI_FIRSTBIT_MSB, SPI_BAUDRATEPRESCALER_2, SPI_MODE_MASTER,

            SPI_CLOCKPOLARITY_HIGH, SPI_CLOCKPHASE_2EDGE,

            SPI_DATADIRECTION_2LINES_FULLDUPLEX, SPI_NSS_SOFT, 0x07);

   SPI_Cmd(ENABLE);

   GPIO_Init(SPI_CS , SPI_Pin_CS, GPIO_MODE_OUT_PP_HIGH_FAST);

   GPIO_WriteHigh(SPI_CS, SPI_Pin_CS)

}

/*

写使能

*/

void SPI_FLASH_WriteEnable(void)

{

  /* Select the FLASH: Chip Select low */

  SPI_FLASH_CS_LOW();

  /* Send "Write Enable" instruction */

  SPI_FLASH_SendByte(WREN);

  /* Deselect the FLASH: Chip Select high */

  SPI_FLASH_CS_HIGH();

}

/**

发送一个字节的数据

*/

u8 SPI_FLASH_SendByte(u8 byte)

{

 while (SPI_GetFlagStatus( SPI_FLAG_TXE) == RESET);

 SPI_SendData(byte);

  while (SPI_GetFlagStatus(SPI_FLAG_RXNE) == RESET);

  return SPI_ReceiveData();  

 }

/*

等待写数据结束

*/

void SPI_FLASH_WaitForWriteEnd(void)

{

  u8 FLASH_Status = 0;

  SPI_FLASH_CS_LOW();

  SPI_FLASH_SendByte(RDSR);

  do

  {

    /* Send a dummy byte to generate the clock needed by the FLASH

    FLASH_Status = SPI_FLASH_SendByte(Dummy_Byte);

 }

  while ((FLASH_Status & WIP_Flag) == SET); /* Write in progress */

  SPI_FLASH_CS_HIGH();

}

/*

写一页数据

*/

void SPI_FLASH_PageWrite(u8* pBuffer, u32 WriteAddr, u16 NumByteToWrite)

{

  SPI_FLASH_WriteEnable();

  SPI_FLASH_CS_LOW();

 SPI_FLASH_SendByte(WRITE);

  /****************************************************************/

  /* Send WriteAddr high nibble address byte to write to */

  SPI_FLASH_SendByte((WriteAddr & 0xFF0000) >> 16);

  /* Send WriteAddr medium nibble address byte to write to */

  SPI_FLASH_SendByte((WriteAddr & 0xFF00) >> 8);

  /* Send WriteAddr low nibble address byte to write to */

  SPI_FLASH_SendByte(WriteAddr & 0xFF);

 /*****************************************************************/

  /* while there is data to be written on the FLASH */

  while (NumByteToWrite--)

  {

    /* Send the current byte */

    SPI_FLASH_SendByte(*pBuffer);

    /* Point on the next byte to be written */

    pBuffer++;

  }

  SPI_FLASH_CS_HIGH();

  SPI_FLASH_WaitForWriteEnd();

}

/*

写BUFFER数据

*/

void SPI_FLASH_BufferWrite(u8* pBuffer, u32 WriteAddr, u16 NumByteToWrite)

{

  u8 NumOfPage = 0, NumOfSingle = 0, Addr = 0, count = 0, temp = 0;

  Addr = WriteAddr % SPI_FLASH_PageSize;// 判断是否是页对齐

  count = SPI_FLASH_PageSize - Addr;   //一页里的第几个

  NumOfPage =  NumByteToWrite / SPI_FLASH_PageSize;

  NumOfSingle = NumByteToWrite % SPI_FLASH_PageSize;

  if (Addr == 0) /* WriteAddr is SPI_FLASH_PageSize aligned  */

  {

    if (NumOfPage == 0) /* NumByteToWrite < SPI_FLASH_PageSize */

    {

      SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumByteToWrite);

    }

    else /* NumByteToWrite > SPI_FLASH_PageSize */

    {

      while (NumOfPage--)

      {

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, SPI_FLASH_PageSize);

        WriteAddr +=  SPI_FLASH_PageSize;

        pBuffer += SPI_FLASH_PageSize;

      }

      SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumOfSingle);

    }

  }

  else /* WriteAddr is not SPI_FLASH_PageSize aligned  */

  {

    if (NumOfPage == 0) /* NumByteToWrite < SPI_FLASH_PageSize */

    {

      if (NumOfSingle > count)

      { /* (NumByteToWrite + WriteAddr) > SPI_FLASH_PageSize */

        temp = NumOfSingle - count;

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, count);

        WriteAddr +=  count;

        pBuffer += count;

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, temp);

      }

      else

      {

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumByteToWrite);

      }

    }

    else /* NumByteToWrite > SPI_FLASH_PageSize */

    {

      NumByteToWrite -= count;

      NumOfPage =  NumByteToWrite / SPI_FLASH_PageSize;

      NumOfSingle = NumByteToWrite % SPI_FLASH_PageSize;

      SPI_FLASH_PageWrite(pBuffer, WriteAddr, count);

      WriteAddr +=  count;

      pBuffer += count;

      while (NumOfPage--)

      {

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, SPI_FLASH_PageSize);

        WriteAddr +=  SPI_FLASH_PageSize;

        pBuffer += SPI_FLASH_PageSize;

      }

      if (NumOfSingle != 0)

      {

        SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumOfSingle);

      }

    }

  }

}

/*

读一个buffer数据

*/

void SPI_FLASH_BufferRead(u8* pBuffer, u32 ReadAddr, u16 NumByteToRead)

{

  /* Select the FLASH: Chip Select low */

  SPI_FLASH_CS_LOW();

  SPI_FLASH_SendByte(READ);

  /* Send ReadAddr high nibble address byte to read from */

  SPI_FLASH_SendByte((ReadAddr & 0xFF0000) >> 16);

  /* Send ReadAddr medium nibble address byte to read from */

  SPI_FLASH_SendByte((ReadAddr& 0xFF00) >> 8);

  /* Send ReadAddr low nibble address byte to read from */

  SPI_FLASH_SendByte(ReadAddr & 0xFF);

  while (NumByteToRead--) /* while there is data to be read */

  {

    /* Read a byte from the FLASH */

    *pBuffer = SPI_FLASH_SendByte(Dummy_Byte);

    /* Point to the next location where the byte read will be saved */

    pBuffer++;

  }

  SPI_FLASH_CS_HIGH();

}