void uart_init(u32 bound){
    //GPIO埠設定
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
	 
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE);	//使能USART1，GPIOA時鐘
     //USART1_TX   PA.9
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;	//複用推輓輸出
    GPIO_Init(GPIOA, &GPIO_InitStructure);
   
    //USART1_RX	  PA.10
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//浮空輸入
    GPIO_Init(GPIOA, &GPIO_InitStructure);  

   //Usart1 NVIC 配置

    NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//搶佔優先順序3
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;		//子優先順序3
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;			//IRQ通道使能
	NVIC_Init(&NVIC_InitStructure);	//根據指定的引數初始化VIC暫存器
  
   //USART 初始化設定

	USART_InitStructure.USART_BaudRate = bound;//一般設定為9600;
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字長為8位資料格式
	USART_InitStructure.USART_StopBits = USART_StopBits_1;//一個停止位
	USART_InitStructure.USART_Parity = USART_Parity_No;//無奇偶校驗位
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//無硬體資料流控制
	USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;	//收發模式

    USART_Init(USART1, &USART_InitStructure); //初始化串列埠
    USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//開啟中斷
    USART_Cmd(USART1, ENABLE);                    //使能串列埠 

}