/*
*说明：
*PA9:USART1_TX;PA10:USART1_RX
*/
#include "stm32f10x.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_usart.h"
#include "stm32f10x_exti.h"
#include "system_stm32f10x.h"
#include "misc.h"

void RCC_Configuration(void);
void GPIO_Configuration(void); 
void USART_Configuration(void);
void NVIC_Configuration(void);

int main()
{
    SystemInit();//72m
    
    RCC_Configuration();
    GPIO_Configuration(); 
    USART_Configuration();
    NVIC_Configuration();
              
    GPIO_ResetBits(GPIOE,GPIO_Pin_5);                                              
    while(1);
}

void RCC_Configuration(void)  
{   
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOE|RCC_APB2Periph_AFIO,ENABLE);  
  RCC_APB1PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
} 

void GPIO_Configuration(void)  
{  
  GPIO_InitTypeDef GPIO_InitStructure; 
  
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;             //CS_485
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;      //推挽输出
  GPIO_Init(GPIOE, &GPIO_InitStructure);   
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;             //管脚2
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;       //复用推挽输出
  GPIO_Init(GPIOA, &GPIO_InitStructure);                //TX初始化
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;             //管脚3
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; //浮空输入        
  GPIO_Init(GPIOA, &GPIO_InitStructure);                //RX初始化
} 

void USART_Configuration(void)//串口初始化函数
{
    //串口参数初始化  
    USART_InitTypeDef USART_InitStructure;               //串口设置恢复默认参数
    //初始化参数设置
    USART_InitStructure.USART_BaudRate = 9600;                  //波特率9600
    USART_InitStructure.USART_WordLength = USART_WordLength_8b; //字长8位
    USART_InitStructure.USART_StopBits = USART_StopBits_1;      //1位停止字节
    USART_InitStructure.USART_Parity = USART_Parity_No;         //无奇偶校验
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无流控制
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;//打开Rx接收和Tx发送功能
    USART_Init(USART2,&USART_InitStructure);                   //初始化
    
    USART_ITConfig(USART2,USART_IT_TXE,ENABLE);                //允许串口1发送中断。
    USART_ITConfig(USART2,USART_IT_RXNE,ENABLE);               //允许串口1接收中断。
    USART_Cmd(USART2,ENABLE);                                  //启动串口
    USART_ClearFlag(USART2,USART_FLAG_TC);                     //发送完成标志位
} 
void NVIC_Configuration(void)//配置中断优先级  
{  
  NVIC_InitTypeDef NVIC_InitStructure;  
    
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);  
    
  NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;  
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;  
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;  
  NVIC_Init(&NVIC_InitStructure);  
}  

#include "..\include\stm32f10x.h" 
#include "..\include\stm32f10x_it.h"
#include "..\include\stm32f10x_gpio.h"
#include "..\include\stm32f10x_usart.h"

void delay_ms(u16 time)     
{    
  u16 i=0;    
  while(time--)     
  {    
    i=12000;    
    while(i--);    
  }    
} 

void USART2_IRQHandler(void)
{
  u8 RX_dat;
  
  if(USART_GetITStatus(USART2,USART_IT_RXNE)==SET)//USART_IT_RXNE：接收中断
  { 
    RX_dat=USART_ReceiveData(USART2);    
    GPIO_SetBits(GPIOE,GPIO_Pin_5);
    delay_ms(1);
   
    USART_SendData(USART2,RX_dat);   
    while(USART_GetFlagStatus(USART2,USART_FLAG_TXE) == RESET){} //发送数据寄存器空标志位
    delay_ms(2);
    GPIO_ResetBits(GPIOE,GPIO_Pin_5);
  }   
}