STM32F407ZE 通過(guò)串口發(fā)送接收PC端串口助手消息，并控制LED燈的亮滅

具體代碼解析如下：

ustart.h部分

#ifndef USTART_H
#define USTART_H

#include <stm32f4xx.h>
#include <stm32f4xx_usart.h>
#include "sys.h"

void USART1_Init();
void USART_SendString(USART_TypeDef* USARTx, char *DataString);
#endif

ustart.c部分

#include "ustart.h"
#include <string.h>

void USART1_Init()
{
	GPIO_InitTypeDef 	GPIOInit_Struct;
	USART_InitTypeDef 	USARTInit_Struct;
	
	//1、使能時(shí)鐘
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
	
	//2、初始化對(duì)應(yīng)的IO引腳復(fù)用為USART1功能
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);
	
	GPIOInit_Struct.GPIO_Pin 	= GPIO_Pin_9 | GPIO_Pin_10;
	GPIOInit_Struct.GPIO_Mode	= GPIO_Mode_AF;
	GPIOInit_Struct.GPIO_OType	= GPIO_OType_PP;
	GPIOInit_Struct.GPIO_Speed 	= GPIO_Fast_Speed;
	GPIOInit_Struct.GPIO_PuPd	= GPIO_PuPd_UP;
	GPIO_Init(GPIOA,&GPIOInit_Struct);
	
	//將PA9  PA10復(fù)用為USART1功能
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);
	
	//3、USART1初始化
	USARTInit_Struct.USART_BaudRate 	= 115200; 								//波特率
	USARTInit_Struct.USART_Parity		= USART_Parity_No;						//無(wú)校驗(yàn)位
	USARTInit_Struct.USART_StopBits		= USART_StopBits_1;						//1位停止位
	USARTInit_Struct.USART_WordLength	= USART_WordLength_8b;					//8位數(shù)據(jù)位
	USARTInit_Struct.USART_Mode			= USART_Mode_Rx | USART_Mode_Tx;		//收發(fā)模式
	USARTInit_Struct.USART_HardwareFlowControl	= USART_HardwareFlowControl_None;//無(wú)硬件控制流
	USART_Init(USART1,&USARTInit_Struct);
	
	//4、開(kāi)啟串口
	USART_Cmd(USART1,ENABLE);
}

void USART_SendString(USART_TypeDef* USARTx, char *DataString)
{
	int i = 0;
	USART_ClearFlag(USARTx,USART_FLAG_TC);										//發(fā)送字符前清空標(biāo)志位（否則缺失字符串的第一個(gè)字符）
	while(DataString[i] != '\0')												//字符串結(jié)束符
	{
		USART_SendData(USARTx,DataString[i]);									//每次發(fā)送字符串的一個(gè)字符
		while(USART_GetFlagStatus(USARTx,USART_FLAG_TC) == 0);					//等待數(shù)據(jù)發(fā)送成功
		USART_ClearFlag(USARTx,USART_FLAG_TC);									//發(fā)送字符后清空標(biāo)志位
		i++;
	}
}

main.c部分（接收PC端發(fā)送來(lái)的單個(gè)字符）

#include <stm32f4xx.h> 
#include "led.h"
#include "ustart.h"

int main()
{
	LED_Init();															//LED燈初始化
	USART1_Init();														//串口初始化
	USART_SendString(USART1, "Hello world!\r\n");						//發(fā)送字符串
	
	char USART1_ReceiveData = 0;										//接收PC端發(fā)送過(guò)來(lái)的字符
	USART_ClearFlag(USART1,USART_FLAG_RXNE);							//接收前先清空標(biāo)志位
	while(1)
	{
		if(USART_GetFlagStatus(USART1,USART_FLAG_RXNE) == 1)			//USART_FLAG_RXNE判斷數(shù)據(jù)，== 1則有數(shù)據(jù)
		{
			USART1_ReceiveData = USART_ReceiveData(USART1);				//通過(guò)USART1串口接收字符
			USART_ClearFlag(USART1,USART_FLAG_RXNE);					//接收后先清空標(biāo)志位
		}
		
		if( '1' == USART1_ReceiveData )									//如果數(shù)據(jù)為1，LED1燈電平翻轉(zhuǎn)
		{
			PFout(9) = !PFout(9);
		}
		
		if( '2' == USART1_ReceiveData )									//如果數(shù)據(jù)為2，LED2燈電平翻轉(zhuǎn)
		{
			PFout(10) = !PFout(10);
		}
		USART1_ReceiveData = 0;											//數(shù)據(jù)清零
	}
}

sys.h部分：

#ifndef __SYS_H
#define __SYS_H	 
#include "stm32f4xx.h" 

//IO口操作宏定義
#define BITBAND(addr, bitnum) ((addr & 0xF0000000)+0x2000000+((addr & 0xFFFFF)<<5)+(bitnum<<2)) 
#define MEM_ADDR(addr)  *((volatile unsigned long  *)(addr)) 
#define BIT_ADDR(addr, bitnum)   MEM_ADDR(BITBAND(addr, bitnum)) 
//IO口地址映射
#define GPIOA_ODR_Addr    (GPIOA_BASE+20) //0x40020014
#define GPIOB_ODR_Addr    (GPIOB_BASE+20) //0x40020414 
#define GPIOC_ODR_Addr    (GPIOC_BASE+20) //0x40020814 
#define GPIOD_ODR_Addr    (GPIOD_BASE+20) //0x40020C14 
#define GPIOE_ODR_Addr    (GPIOE_BASE+20) //0x40021014 
#define GPIOF_ODR_Addr    (GPIOF_BASE+20) //0x40021414    
#define GPIOG_ODR_Addr    (GPIOG_BASE+20) //0x40021814   
#define GPIOH_ODR_Addr    (GPIOH_BASE+20) //0x40021C14    
#define GPIOI_ODR_Addr    (GPIOI_BASE+20) //0x40022014     

#define GPIOA_IDR_Addr    (GPIOA_BASE+16) //0x40020010 
#define GPIOB_IDR_Addr    (GPIOB_BASE+16) //0x40020410 
#define GPIOC_IDR_Addr    (GPIOC_BASE+16) //0x40020810 
#define GPIOD_IDR_Addr    (GPIOD_BASE+16) //0x40020C10 
#define GPIOE_IDR_Addr    (GPIOE_BASE+16) //0x40021010 
#define GPIOF_IDR_Addr    (GPIOF_BASE+16) //0x40021410 
#define GPIOG_IDR_Addr    (GPIOG_BASE+16) //0x40021810 
#define GPIOH_IDR_Addr    (GPIOH_BASE+16) //0x40021C10 
#define GPIOI_IDR_Addr    (GPIOI_BASE+16) //0x40022010 
 
//STM32中  對(duì)寄存器的訪問(wèn)  是不能單獨(dú)訪問(wèn)寄存器的單個(gè)bit  只能以32bit地址訪問(wèn)寄存器
//這些位為只寫(xiě)形式，只能在字(word)--4byte、半字2byte 或字節(jié)模式下訪問(wèn) 
//IO口操作,只對(duì)單一的IO口!
//確保n的值小于16!
#define PAout(n)   BIT_ADDR(GPIOA_ODR_Addr,n)  //輸出 
#define PAin(n)    BIT_ADDR(GPIOA_IDR_Addr,n)  //輸入 

#define PBout(n)   BIT_ADDR(GPIOB_ODR_Addr,n)  //輸出 
#define PBin(n)    BIT_ADDR(GPIOB_IDR_Addr,n)  //輸入 

#define PCout(n)   BIT_ADDR(GPIOC_ODR_Addr,n)  //輸出 
#define PCin(n)    BIT_ADDR(GPIOC_IDR_Addr,n)  //輸入 

#define PDout(n)   BIT_ADDR(GPIOD_ODR_Addr,n)  //輸出 
#define PDin(n)    BIT_ADDR(GPIOD_IDR_Addr,n)  //輸入 

#define PEout(n)   BIT_ADDR(GPIOE_ODR_Addr,n)  //輸出 
#define PEin(n)    BIT_ADDR(GPIOE_IDR_Addr,n)  //輸入

#define PFout(n)   BIT_ADDR(GPIOF_ODR_Addr,n)  //輸出 
#define PFin(n)    BIT_ADDR(GPIOF_IDR_Addr,n)  //輸入

#define PGout(n)   BIT_ADDR(GPIOG_ODR_Addr,n)  //輸出 
#define PGin(n)    BIT_ADDR(GPIOG_IDR_Addr,n)  //輸入

#define PHout(n)   BIT_ADDR(GPIOH_ODR_Addr,n)  //輸出 
#define PHin(n)    BIT_ADDR(GPIOH_IDR_Addr,n)  //輸入

#define PIout(n)   BIT_ADDR(GPIOI_ODR_Addr,n)  //輸出 
#define PIin(n)    BIT_ADDR(GPIOI_IDR_Addr,n)  //輸入


#endif

開(kāi)啟串口終端接收PC端串口助手發(fā)送過(guò)來(lái)的字符

ustart.c部分

#include "ustart.h"
#include <string.h>

void USART1_Init()
{
	GPIO_InitTypeDef 	GPIOInit_Struct;
	USART_InitTypeDef 	USARTInit_Struct;
	NVIC_InitTypeDef  	USARTNVIC_Struct;
	
	//1、使能時(shí)鐘
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
	
	//2、初始化對(duì)應(yīng)的IO引腳復(fù)用為USART1功能
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);
	
	GPIOInit_Struct.GPIO_Pin 	= GPIO_Pin_9 | GPIO_Pin_10;
	GPIOInit_Struct.GPIO_Mode	= GPIO_Mode_AF;
	GPIOInit_Struct.GPIO_OType	= GPIO_OType_PP;
	GPIOInit_Struct.GPIO_Speed 	= GPIO_Fast_Speed;
	GPIOInit_Struct.GPIO_PuPd	= GPIO_PuPd_UP;
	GPIO_Init(GPIOA,&GPIOInit_Struct);
	
	//將PA9  PA10復(fù)用為USART1功能
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);
	
	//3、USART1初始化
	USARTInit_Struct.USART_BaudRate 	= 115200; 								//波特率
	USARTInit_Struct.USART_Parity		= USART_Parity_No;						//無(wú)校驗(yàn)位
	USARTInit_Struct.USART_StopBits		= USART_StopBits_1;						//1位停止位
	USARTInit_Struct.USART_WordLength	= USART_WordLength_8b;					//8位數(shù)據(jù)位
	USARTInit_Struct.USART_Mode			= USART_Mode_Rx | USART_Mode_Tx;		//收發(fā)模式
	USARTInit_Struct.USART_HardwareFlowControl	= USART_HardwareFlowControl_None;//無(wú)硬件控制流
	USART_Init(USART1,&USARTInit_Struct);
	
	//開(kāi)啟串口中斷
	USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
	
	USARTNVIC_Struct.NVIC_IRQChannel = USART1_IRQn;//stm32f4xx.h
	USARTNVIC_Struct.NVIC_IRQChannelPreemptionPriority = 0;
	USARTNVIC_Struct.NVIC_IRQChannelSubPriority        = 0;
	USARTNVIC_Struct.NVIC_IRQChannelCmd	= ENABLE;
	NVIC_Init(&USARTNVIC_Struct);
	
	//4、開(kāi)啟串口
	USART_Cmd(USART1,ENABLE);
}

void USART_SendString(USART_TypeDef* USARTx, char *DataString)
{
	int i = 0;
	USART_ClearFlag(USARTx,USART_FLAG_TC);										//發(fā)送字符前清空標(biāo)志位（否則缺失字符串的第一個(gè)字符）
	while(DataString[i] != '\0')												//字符串結(jié)束符
	{
		USART_SendData(USARTx,DataString[i]);									//每次發(fā)送字符串的一個(gè)字符
		while(USART_GetFlagStatus(USARTx,USART_FLAG_TC) == 0);					//等待數(shù)據(jù)發(fā)送成功
		USART_ClearFlag(USARTx,USART_FLAG_TC);									//發(fā)送字符后清空標(biāo)志位
		i++;
	}
}

void USART1_IRQHandler(void)													//串口中斷執(zhí)行函數(shù)
{
	char USART1_ReceiveData = 0;												//接收PC端發(fā)送過(guò)來(lái)的字符
	
	if(USART_GetFlagStatus(USART1,USART_IT_RXNE) == 1)							//USART_FLAG_RXNE判斷數(shù)據(jù)，== 1則有數(shù)據(jù)
	{		
		USART1_ReceiveData = USART_ReceiveData(USART1);							//通過(guò)USART1串口接收字符
		USART_ClearFlag(USART1,USART_IT_RXNE);									//接收后先清空標(biāo)志位
	}
	
	if( '1' == USART1_ReceiveData )												//如果數(shù)據(jù)為1，LED1燈電平翻轉(zhuǎn)
	{
		PFout(9) = !PFout(9);
	}
	
	if( '2' == USART1_ReceiveData )												//如果數(shù)據(jù)為2，LED2燈電平翻轉(zhuǎn)
	{
		PFout(10) = !PFout(10);
	}
}

ustart.h部分

#ifndef USTART_H
#define USTART_H

#include <stm32f4xx.h>
#include <stm32f4xx_usart.h>
#include "sys.h"

void USART1_Init();
void USART_SendString(USART_TypeDef* USARTx, char *DataString);
#endif

main.c部分

#include <stm32f4xx.h> //該頭文件作用和reg51.h是一樣的
#include "led.h"
#include "ustart.h"

int main()
{
	LED_Init();
	USART1_Init();
	USART_SendString(USART1, "Hello world!\r\n");

}