大家好：
    我的程序在读写sst25vf512只能读，不能写，读取ID都是正确的，擦除也可以，就是不能写。我觉得可能是初始化时某个寄存器没有配置正确，但是不知道怎么弄，特请教大家。下面是程序
#define SPI_FLASH_PageSize 256 #define WRITE      0x02  /* Write to Memory instruction */
#define WRSR       0x01  /* Write Status Register instruction */
#define WREN       0x06  /* Write enable instruction */ #define READ       0x03  /* Read from Memory instruction */
#define RDSR       0x05  /* Read Status Register instruction  */
#define RDID       0x90  /* Read identification */
#define SE         0x20  /* Sector Erase instruction */
#define BE         0x52  /* Bulk Erase instruction */ #define WIP_Flag   0x01  /* Write In Progress (WIP) flag */ #define Dummy_Byte 0xff
/* Select SPI FLASH: ChipSelect pin low  */
#define SPI_FLASH_CS_LOW()     GPIO_ResetBits(GPIOC, GPIO_Pin_5)
/* Deselect SPI FLASH: ChipSelect pin high */
#define SPI_FLASH_CS_HIGH()    GPIO_SetBits(GPIOC, GPIO_Pin_5)
 void SPI_FLASH_Init(void)
{
  SPI_InitTypeDef  SPI_InitStructure;
  GPIO_InitTypeDef GPIO_InitStructure;
  
  /* Enable SPI1 GPIOA and GPIOB clocks */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1 | RCC_APB2Periph_GPIOA |RCC_APB2Periph_GPIOB, ENABLE);
 
  /* Configure SPI1 pins: NSS, SCK, MISO and MOSI */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_Init(GPIOA, &GPIO_InitStructure);   /* Configure PC.05 as Output push-pull, used as Flash Chip select */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_Init(GPIOC, &GPIO_InitStructure);   /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();   /* SPI1 configuration */
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial = 7;
  SPI_Init(SPI1, &SPI_InitStructure);
 
  /* Enable SPI1  */
  SPI_Cmd(SPI1, ENABLE); 
 
}
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;
  count = SPI_FLASH_PageSize - Addr;
  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);
      }
    }
  }
}
void SPI_FLASH_PageWrite(u8* pBuffer, u32 WriteAddr, u16 NumByteToWrite)
{
  /* Enable the write access to the FLASH */
  SPI_FLASH_WriteEnable();
 
  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();
  /* Send "Write to Memory " instruction */
  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++;
  }
 
  /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();
 
  /* Wait the end of Flash writing */
  SPI_FLASH_WaitForWriteEnd();
}
void SPI_FLASH_WriteEnable(void)
{
  vu8 sta;
  /* 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();
}
此帖出自小平头技术问答