其他串口的使用

nanyechenxing

void uart_initial(u32 bound)

{

//   float temp;

   GPIO_InitTypeDef GPIO_InitStructure;

   USART_InitTypeDef USART_InitStructure;

   NVIC_InitTypeDef NVIC_InitStructure;

   RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2 , ENABLE);

   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);//(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE);

   /*Confugure USART2 */

   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOA, &GPIO_InitStructure);    

/* Configure USART2 Rx (PA.3) as input floating */

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_Init(GPIOA, &GPIO_InitStructure);

/*USART2 mode  configure */

    USART_InitStructure.USART_BaudRate = bound;//一般设置为9600或者115200;

USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式

USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位

USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //收发模式

    USART_Init(USART2, &USART_InitStructure); //初始化串口

#if EN_USART1_RX  //如果使能了接收  

   //Usart2 NVIC 配置

    NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//抢占优先级3

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //子优先级3

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能

NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化NVIC寄存器

   

    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);//开启中断

#endif

    USART_Cmd(USART2, ENABLE);//使能了串口2

}

我配置了串口2 

但是我主函数
使用了int main(void)

{

 uart_initial(9600);

 printf("hello my world");

  

}

输出不了数据 ，怎么回事
原子哥

正点原子

回复【楼主位】nanyechenxing:
---------------------------------
系统时钟都不配置...
能用才怪哦

nanyechenxing

回复【2楼】正点原子:
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回复【2楼】正点原子:
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回复【2楼】正点原子:
------------------------原子哥威武