作者：jxchenshen

USART串口学习

 

USART串口

串口配置过程

  • 串口时钟使能、GPIO时钟使能RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //使能USART1，GPIOA时钟
  • 串口复位

USART_DeInit();//非必须操作配置

  • GPIO端口模式配置

GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.9
//USART1_RX GPIOA.10初始化
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;//PA10
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//浮空输入
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.10

  • 串口参数初始化

USART_InitTypeDef USART_InitStructure;
USART_InitStructure.USART_BaudRate = 115200;//串口波特率
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(USART1, &USART_InitStructure); //初始化串口1

  • 开启中断并初始化NVIC

USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_InitStructure.NVIC_IRQChannel = USART1_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VIC寄存器

  • 使能串口

USART_Cmd(USART1, ENABLE);

  • 编写中断初始化处理函

void USART1_IRQHandler(void)
{
u8 Res;
if(USART_GetITStatus(USART1, USART_IT_RXNE))
{
Res =USART_ReceiveData(USART1); //读取接收到的数据
USART_SendData(USART1,Res);
}

}

  • 串口数据收发

void USART_SendData();//发送数据到串口
uint16_t USART_ReceiveData();//读取接收数据

  • 串口函数编程

  • C文件

#include “usart.h”
void My_USART_Init(void)
{

GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //使能USART1，GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.9

//USART1_RX GPIOA.10初始化
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;//PA10
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//浮空输入
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.10
USART_InitStructure.USART_BaudRate = 115200;//串口波特率
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(USART1, &USART_InitStructure); //初始化串口1
USART_Cmd(USART1, ENABLE);
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
//Usart1 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = USART1_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VIC寄存器
}
void USART1_IRQHandler(void)
{
u8 Res;
if(USART_GetITStatus(USART1, USART_IT_RXNE))
{
Res =USART_ReceiveData(USART1); //读取接收到的数据
USART_SendData(USART1,Res);
}

}

  • .h文件

#ifndef __USART_H
#define __USART_H
#include “stm32f10x.h”
void My_USART_Init(void);
#endif

  • main函数

#include “stm32f10x.h”
#include “lcd.h”
#include “key.h”
#include “delay.h”
#include “usart.h”
int main(void)
{
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2 );
My_USART_Init();
while(1)
{

}
}

 

本文出自：https://blog.csdn.net/weixin_44918643/article/details/115362998