出現(xiàn)的問題：在使用sscom32串口調(diào)試助手，首字符出現(xiàn)亂碼“?tart?tart?tart?tart?tart?tart”

原因：波特率過高

解決辦法：將波特率設(shè)置的低一點(diǎn)，通常9600即可

現(xiàn)象：亂碼為波特率較高; 正常顯示波特率較低

函數(shù)代碼如下：

int main(void)

{

USART1_Init();

printf("Start");

}

#include "usart1.h"

void USART1_Init(void)

{

USART1_GPIO_Config();

USART1_Structure_Config();

USART_Cmd(USART1, ENABLE);

}

static void USART1_GPIO_Config(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;

// GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_Init(GPIOA, &GPIO_InitStructure);

}

static void USART1_Structure_Config(void)

{

USART_InitTypeDef USART_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

USART_InitStructure.USART_BaudRate = 1200;

USART_InitStructure.USART_WordLength = USART_WordLength_8b;

USART_InitStructure.USART_StopBits = USART_StopBits_1;

USART_InitStructure.USART_Parity = USART_Parity_No ;

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_Init(USART1, &USART_InitStructure);

}

int fputc(int ch, FILE *f)

{

USART_ClearFlag(USART1,USART_FLAG_TC);//清除串口1發(fā)送中斷--否則第一個(gè)數(shù)不會(huì)發(fā)送

USART_SendData(USART1, (uint16_t) ch);

while(USART_GetFlagStatus(USART1, USART_FLAG_TC)!= SET);

return ch;

}