新手stm32f1103串口问题求助？

只看该作者 · 2019-3-8 21:19

STM32F103ZET6的串口1发送数据总是在上电后第一次发送数据前几位乱码，之后正常，再等一会后再发数据有乱码在发送就正常，求取大神看看什么问题！下面是程序
void USART1_Config(unsigned int bound)
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

/* ÅäÖÃ´®¿Ú1 £¨USART1£© Ê±ÖÓ*/
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE);
/*´®¿ÚGPIO¶Ë¿ÚÅäÖÃ*/
  /* ÅäÖÃ´®¿Ú1 £¨USART1 Tx (PA.09)£©*/
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* ÅäÖÃ´®¿Ú1 USART1 Rx (PA.10)*/
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* ´®¿Ú1Ä£Ê½£¨USART1 mode£©ÅäÖÃ */
USART_InitStructure.USART_BaudRate = bound;//Ò»°ãÉèÖÃÎª9600;
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_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStructure);
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//¿ªÆôÖÐ¶Ï

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

/* Ê¹ÄÜ´®¿Ú1ÖÐ¶Ï */
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
/*IRQÍ¨µÀÊ¹ÄÜ*/
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
/*¸ù¾ÝNVIC_InitStructÖÐÖ¸¶¨µÄ²ÎÊý³õÊ¼»¯ÍâÉèNVIC¼Ä´æÆ÷USART1*/
NVIC_Init(&NVIC_InitStructure);

USART_Cmd(USART1, ENABLE); //Ê¹ÄÜ´®¿Ú
}

int fputc(int ch, FILE *f)
{
// ½«PrintfÄÚÈÝ·¢Íù´®¿Ú
USART_SendData(USART1, (unsigned char) ch);
while( USART_GetFlagStatus(USART1,USART_FLAG_TC)!= SET);
return (ch);
}

只看该作者 · 2019-3-9 09:19

int fputc(int ch, FILE *f)
{
      USART1->SR;
      USART_SendData(USART1, (unsigned char) ch);
      while(USART_GetFlagStatus(USART1,USART_FLAG_TC)!=SET);
      return(ch);
}

试试看这个代码