void W25Q128_Config(void)
{
  SPI_InitTypeDef  SPI_InitStructure;
  GPIO_InitTypeDef GPIO_InitStructure;

  //打开SPI1的时钟
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

  //打开GPIOB端口的时钟
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB,ENABLE);
  
  //选择IO口的复用功能
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource3, GPIO_AF_SPI1);		//SCK
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource4, GPIO_AF_SPI1);		//MISO
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource5, GPIO_AF_SPI1);     	//MOSI

  GPIO_InitStructure.GPIO_Mode 	= GPIO_Mode_AF;					//复用模式
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_DOWN;
  GPIO_InitStructure.GPIO_Pin 	= GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  //配置CS片选引脚  输出模式  
  GPIO_InitStructure.GPIO_Pin 	= GPIO_Pin_14;
  GPIO_InitStructure.GPIO_Mode 	= GPIO_Mode_OUT;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_PuPd 	= GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
    
  //片选引脚，空闲状态为高电平
  W25Q128_CS(1);

  //配置SPI1  W25Q128存储IC支持模式0和模式3
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;	//全双工
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;							//主模式
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;						//8bit数据位
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;							//时钟极性  1
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;							//时钟相位  1    11 --模式3
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;								//软件控制CS片选	
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;	

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;					//高位先出
  SPI_Init(SPI1, &SPI_InitStructure);

  //使能SPI1
  SPI_Cmd(SPI1, ENABLE);

}

//发送一个字节，并且会得到一个字节
uint8_t W25Q128_SendByte(uint8_t 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);
}


//读取设备ID   0x17
uint8_t W25Q128_ReadDeviceID(void)
{
	uint8_t device_id = 0;
	
	//1.把片选引脚拉低
	W25Q128_CS(0);
	
	//2.MCU发送指令  0x90
	W25Q128_SendByte(0x90);
	
	//3.MCU发送地址
	W25Q128_SendByte(0x00);
	W25Q128_SendByte(0x00);
	W25Q128_SendByte(0x00);

	//4.MCU提供脉冲，得到厂商ID 
	W25Q128_SendByte(0xFF);
	
	//5.MCU提供脉冲，得到设备ID
	device_id = W25Q128_SendByte(0xFF);
	
	//6.把片选引脚拉高
	W25Q128_CS(1);
	
	return device_id;
}


int main()
{
	uint8_t buf[128] = {0};
	
	//1.硬件的初始化
	USART1_Config(9600);
	W25Q128_Config();
	
	//2.读取W25Q128的设备ID
	sprintf((char *)buf,"Device ID = %#X\r\n",W25Q128_ReadDeviceID());
	USART1_SendString((char *)buf);
	
	while(1)
	{
		
	}
}