各位大神:
我想读取W24X40的ID信息,然后在串口显示,但是串口显示全是零,请指教一下我程序哪里出错啦?
读三个ID的代码是下面的
u8 SPI_FLASH_SendByte(u8 BYTE)
{
  while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
   SPI_I2S_SendData(SPI1, BYTE);
  while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);
   return SPI_I2S_ReceiveData(SPI1);
}
u32 SPI_FLASH_ReadDeviceID(void)
{
  u8 tmp0;
  GPIO_ResetBits(GPIOA, GPIO_Pin_4);
  SPI_FLASH_SendByte(0xAB);
  SPI_FLASH_SendByte(0xFF);
  SPI_FLASH_SendByte(0xFF);
  SPI_FLASH_SendByte(0xFF);
  tmp0 = SPI_FLASH_SendByte(0xFF);
  GPIO_SetBits(GPIOA, GPIO_Pin_4);
  return tmp0;
  
}
u32 SPI_FLASH_ReadID(void)
{
  u32 tmp1 = 0,tmp2 = 0,tmp3 = 0,tmp4 = 0;
  GPIO_ResetBits(GPIOA, GPIO_Pin_4);
   SPI_FLASH_SendByte(0x9F);
  tmp1 = SPI_FLASH_SendByte(0xFF);
  tmp1&=0x0FF;
  tmp2 = SPI_FLASH_SendByte(0xFF);
  tmp2&=0x0FF;
  tmp3 = SPI_FLASH_SendByte(0xFF);
  tmp3&=0x0FF;
  GPIO_SetBits(GPIOA, GPIO_Pin_4);
  tmp4 = (tmp1<<16)|(tmp2<<8)|tmp3;
  return tmp4;
  
  }
u16 SPI_FLASH_ReadID1(void)
{
  u16 tmp = 0, tmp1 = 0, tmp2 = 0;
  GPIO_ResetBits(GPIOA, GPIO_Pin_4);
  SPI_FLASH_SendByte(0x90);
  SPI_FLASH_SendByte(0x00);
  SPI_FLASH_SendByte(0x00);
  SPI_FLASH_SendByte(0x00);
  tmp1 = SPI_FLASH_SendByte(0xff);
  tmp2 = SPI_FLASH_SendByte(0xff);
  GPIO_SetBits(GPIOA, GPIO_Pin_4);
  tmp = (tmp1<<8)|tmp2;
  return tmp;
}
下面是输出到串口部分的代码:
while(1)
{
    tp1 = SPI_FLASH_ReadDeviceID();
   tp2 = SPI_FLASH_ReadID();
   tp3 = SPI_FLASH_ReadID1();
   printf(" ID已经读出来！ ");
   GPIO_SetBits(GPIOA, GPIO_Pin_2);
     GPIO_ResetBits(GPIOA, GPIO_Pin_1);
   printf(" ID1=:0x%4x ", tp1);
    printf(" ID2=:0x%4x ", tp2);
   printf(" ID3=:0x%2x ", tp3);
   //while(1);
     ZQ_Delay(1000);
     GPIO_ResetBits(GPIOA, GPIO_Pin_2);
      GPIO_SetBits(GPIOA, GPIO_Pin_1);
   tp1 = SPI_FLASH_ReadDeviceID();
   tp2 = SPI_FLASH_ReadID();
   tp3 = SPI_FLASH_ReadID1();
    printf(" ID 又读出来 ");
   printf(" ID1=:0x%4x ", tp1);
    printf(" ID2=:0x%4x ", tp2);
   printf(" ID3=:0x%2x ", tp3);
     ZQ_Delay(1000);
}
在线求指教啊?
串口的输出结果是这样:
usart1 开启成功
SPI 开启成功
ID已经读出来！
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
ID 又读出来
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
ID已经读出来！
ID1=:0x   0
ID2=:0x3ffff
ID3=:0x 0
ID 又读出来
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
ID已经读出来！
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
ID 又读出来
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
ID已经读出来！
ID1=:0x   0
ID2=:0x   0
ID3=:0x 0
有一次读出来的值还不一样!