stm32串口收发程序

好的，下面是一个基本的 STM32 串口收发程序示例，可以帮助你进行串口通信：

#include "stm32f10x.h"
#include <stdio.h>

#define USART1_DR_Base 0x40013804
#define MAX_STRLEN 100

volatile char received_string[MAX_STRLEN+1];
volatile uint8_t str_received = 0;
volatile uint32_t timer = 0;

void init_USART1(uint32_t baudrate) {
  GPIO_InitTypeDef GPIO_InitStruct;
  USART_InitTypeDef USART_InitStruct;
  NVIC_InitTypeDef NVIC_InitStruct;

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);

  GPIO_InitStruct.GPIO_Pin = GPIO_Pin_9;
  GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOA, &GPIO_InitStruct);

  GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10;
  GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOA, &GPIO_InitStruct);

  USART_InitStruct.USART_BaudRate = baudrate;
  USART_InitStruct.USART_WordLength = USART_WordLength_8b;
  USART_InitStruct.USART_StopBits = USART_StopBits_1;
  USART_InitStruct.USART_Parity = USART_Parity_No;
  USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  USART_InitStruct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
  USART_Init(USART1, &USART_InitStruct);

  USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

  NVIC_InitStruct.NVIC_IRQChannel = USART1_IRQn;
  NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStruct);

  USART_Cmd(USART1, ENABLE);
}

void init_timer(uint32_t frequency) {
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

  TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
  TIM_TimeBaseInitStruct.TIM_Prescaler = 7200-1;
  TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInitStruct.TIM_Period = 10000/frequency-1;
  TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStruct);

  TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);

  NVIC_InitTypeDef NVIC_InitStruct;
  NVIC_InitStruct.NVIC_IRQChannel = TIM2_IRQn;
  NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStruct);

  TIM_Cmd(TIM2, ENABLE);
}

void USART1_IRQHandler(void) {
  if (USART_GetITStatus(USART1, USART_IT_RXNE)) {
    char ch = USART1->DR & 0xFF;
    if ((ch == '\n' || ch == '\r') && str_received == 0) {
      received_string[str_received++] = '\n';
      received_string[str_received] = '\0';
    } else if (str_received < MAX_STRLEN) {
      received_string[str_received++] = ch;
      received_string[str_received] = '\0';
    }
    USART_ClearITPendingBit(USART1, USART_IT_RXNE);
  }
}

void TIM2_IRQHandler(void) {
  if (TIM_GetITStatus(TIM2, TIM_IT_Update)) {
    timer++;
    TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
  }
}

void send_data(char* data) {
  while (*data) {
    while (!(USART1->SR & USART_SR_TXE));
    USART1->DR = (*data++ & 0xFF);
  }
}

int main(void) {
  init_USART1(9600);
  init_timer(1);

  while(1) {
    if (str_received) {
      send_data(received_string);
      str_received = 0;
    }
  }
}

这个示例代码使用了 USART1 和 TIM2 模块来实现串口收发和定时器。在 while 循环中，如果收到了串口数据，则通过串口发送回去。你可以根据自己的需要修改代码中的波特率和其他设置。

希望这个代码示例可以帮到你！