spi_flash.c

STM32所有外设例子程序（需自己修改）

      }
    }
    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);
      }
    }
  }
}

/*******************************************************************************
* Function Name  : SPI_FLASH_BufferRead
* Description    : Reads a block of data from the FLASH.
* Input          : - pBuffer : pointer to the buffer that receives the data read
*                    from the FLASH.
*                  - ReadAddr : FLASH's internal address to read from.
*                  - NumByteToRead : number of bytes to read from the FLASH.
* Output         : None
* Return         : None
*******************************************************************************/
void SPI_FLASH_BufferRead(u8* pBuffer, u32 ReadAddr, u16 NumByteToRead)
{
  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();

  /* Send "Read from Memory " instruction */
  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++;
  }

  /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();
}

/*******************************************************************************
* Function Name  : SPI_FLASH_ReadID
* Description    : Reads FLASH identification.
* Input          : None
* Output         : None
* Return         : FLASH identification
*******************************************************************************/
u32 SPI_FLASH_ReadID(void)
{
  u32 Temp = 0, Temp0 = 0, Temp1 = 0, Temp2 = 0;

  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();

  /* Send "RDID " instruction */
  SPI_FLASH_SendByte(0x9F);

  /* Read a byte from the FLASH */
  Temp0 = SPI_FLASH_SendByte(Dummy_Byte);

  /* Read a byte from the FLASH */
  Temp1 = SPI_FLASH_SendByte(Dummy_Byte);

  /* Read a byte from the FLASH */
  Temp2 = SPI_FLASH_SendByte(Dummy_Byte);

  /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();

  Temp = (Temp0 << 16) | (Temp1 << 8) | Temp2;

  return Temp;
}

/*******************************************************************************
* Function Name  : SPI_FLASH_StartReadSequence
* Description    : Initiates a read data byte (READ) sequence from the Flash.
*                  This is done by driving the /CS line low to select the device,
*                  then the READ instruction is transmitted followed by 3 bytes
*                  address. This function exit and keep the /CS line low, so the
*                  Flash still being selected. With this technique the whole
*                  content of the Flash is read with a single READ instruction.
* Input          : - ReadAddr : FLASH's internal address to read from.
* Output         : None
* Return         : None
*******************************************************************************/
void SPI_FLASH_StartReadSequence(u32 ReadAddr)
{
  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();

  /* Send "Read from Memory " instruction */
  SPI_FLASH_SendByte(READ);

  /* Send the 24-bit address of the address to read from -----------------------*/
  /* Send ReadAddr high nibble address byte */
  SPI_FLASH_SendByte((ReadAddr & 0xFF0000) >> 16);
  /* Send ReadAddr medium nibble address byte */
  SPI_FLASH_SendByte((ReadAddr& 0xFF00) >> 8);
  /* Send ReadAddr low nibble address byte */
  SPI_FLASH_SendByte(ReadAddr & 0xFF);
}

/*******************************************************************************
* Function Name  : SPI_FLASH_ReadByte
* Description    : Reads a byte from the SPI Flash.
*                  This function must be used only if the Start_Read_Sequence
*                  function has been previously called.
* Input          : None
* Output         : None
* Return         : Byte Read from the SPI Flash.
*******************************************************************************/
u8 SPI_FLASH_ReadByte(void)
{
  return (SPI_FLASH_SendByte(Dummy_Byte));
}

/*******************************************************************************
* Function Name  : SPI_FLASH_SendByte
* Description    : Sends a byte through the SPI interface and return the byte
*                  received from the SPI bus.
* Input          : byte : byte to send.
* Output         : None
* Return         : The value of the received byte.
*******************************************************************************/
u8 SPI_FLASH_SendByte(u8 byte)
{
  /* Loop while DR register in not emplty */
  while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

  /* Send byte through the SPI1 peripheral */
  SPI_I2S_SendData(SPI1, byte);

  /* Wait to receive a byte */
  while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);

  /* Return the byte read from the SPI bus */
  return SPI_I2S_ReceiveData(SPI1);
}

/*******************************************************************************
* Function Name  : SPI_FLASH_SendHalfWord
* Description    : Sends a Half Word through the SPI interface and return the
*                  Half Word received from the SPI bus.
* Input          : Half Word : Half Word to send.
* Output         : None
* Return         : The value of the received Half Word.
*******************************************************************************/
u16 SPI_FLASH_SendHalfWord(u16 HalfWord)
{
  /* Loop while DR register in not emplty */
  while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

  /* Send Half Word through the SPI1 peripheral */
  SPI_I2S_SendData(SPI1, HalfWord);

  /* Wait to receive a Half Word */
  while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);

  /* Return the Half Word read from the SPI bus */
  return SPI_I2S_ReceiveData(SPI1);
}

/*******************************************************************************
* Function Name  : SPI_FLASH_WriteEnable
* Description    : Enables the write access to the FLASH.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
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();
}

/*******************************************************************************
* Function Name  : SPI_FLASH_WaitForWriteEnd
* Description    : Polls the status of the Write In Progress (WIP) flag in the
*                  FLASH's status  register  and  loop  until write  opertaion
*                  has completed.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void SPI_FLASH_WaitForWriteEnd(void)
{
  u8 FLASH_Status = 0;

  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();

  /* Send "Read Status Register" instruction */
  SPI_FLASH_SendByte(RDSR);

  /* Loop as long as the memory is busy with a write cycle */
  do
  {
    /* Send a dummy byte to generate the clock needed by the FLASH
    and put the value of the status register in FLASH_Status variable */
    FLASH_Status = SPI_FLASH_SendByte(Dummy_Byte);

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

  /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();
}

/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/