串口异常问题

只看该作者 · 2019-3-6 11:05

我才采用的是STM32F4串口打印，我给固定printf("1");串口调试助手输出却一直是g，具体代码如下：
void USART1_Config()
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
//NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
// USART_DeInit(USART1);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed  = GPIO_Fast_Speed;
GPIO_InitStructure.GPIO_OType  = GPIO_OType_PP;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_Speed  = GPIO_Fast_Speed;
GPIO_InitStructure.GPIO_OType  = GPIO_OType_PP;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_PinAFConfig(GPIOB,GPIO_PinSource6,GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOB,GPIO_PinSource7,GPIO_AF_USART1);

//    NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
//    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//ÇÀÕ¼ÓÅÏÈ¼¶3
//    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //×ÓÓÅÏÈ¼¶3
//    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQÍ¨µÀÊ¹ÄÜ
//    NVIC_Init(&NVIC_InitStructure); //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õÊ¼»¯VIC¼Ä´æÆ÷

USART_InitStructure.USART_BaudRate = 9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No ;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;

USART_Init(USART1, &USART_InitStructure);
// USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
USART_Cmd(USART1, ENABLE);
}

while(1)
{
//printf("%d\r\n",cnt1);
printf("1");
// putchar('1');
// DAC1_Set_Vol(cnt1);
// DAC1_Set_Vol(m1);
  }

请问问题一般怎么找？打算最后再考虑硬件问题