usart.h

多功能MP3代码

#ifndef __USART_H
#define __USART_H
#include "stdio.h"
//注意要包含库:STM32F10xR.LIB,提供USART_SendData()和USART_GetFlagStatus()这两个函数
//正点原子@SCUT
//2008/12/08	  
#ifdef __GNUC__								 
  #define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
  #define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif 
//重定义C语言库函数printf到串口1
PUTCHAR_PROTOTYPE
{										 
	USART_SendData(USART1,(u8)ch);//写一个字符到串口1 
  	while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);//循环发送,直到发送完毕   
  	return ch;
}  	
//中断优先级管理/开启	   
void NVIC_Configuration(void)
{										    	 
	NVIC_InitTypeDef NVIC_InitStructure;	 
	#ifdef  VECT_TAB_RAM  									   
		NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0); 
	#else   							 
		NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);   
	#endif 
  										     
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);	   
	NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure); 								 
} 
//串口1中断服务程序
//注意,读取USARTx->SR能避免莫名其妙的错误
u8 time_set[7]; //时间设置寄存器	
u8 rebuffer[14];//接收缓冲  
u8 recount=0;   //接收完全	    
void USART1_IRQHandler(void)
{
	u8 res;	    
	if(USART1->SR&(1<<5))//接收到数据
	{	 
		res=USART1->DR;   			   
		if(recount<14&&res>47&&res<58)//仅仅接收数据
		{
			rebuffer[recount]=res-'0';//得到ASCII
			recount++;
		}  											     
	}  
} 										 
//初始化IO 串口1
//初始化IO 串口1
void uart_init()
{  	 
	RCC->APB2ENR|=1<<2;   //使能PORTA口时钟  
	RCC->APB2ENR|=1<<14;  //使能串口时钟 
	GPIOA->CRH=0X444444B4;//IO状态设置
		  
	RCC->APB2RSTR|=1<<14;   //复位串口1
	RCC->APB2RSTR&=~(1<<14);//停止复位	   
	//先使能时钟(切记)
   	RCC->APB2ENR|=1<<9;	  //TX
	RCC->APB2ENR|=1<<10;  //RX  
	//波特率设置
 	USART1->BRR=0X1D4C;    //9600波特率(72M时钟)	 
	USART1->CR1|=0X200C;   //1位停止,无校验位.
	//使能接收中断
	USART1->CR1|=1<<8;    //PE中断使能
	USART1->CR1|=1<<5;    //接收缓冲区非空中断使能	
	NVIC_Configuration(); //中断管理，不开启	
}
#endif