T640_DTU/USER/VirtualCOM.c

#include "includes.h"
/*********************************************
使用说明：
1.首先把TIM_TX_Configuration(),TIM_RX_Configuration(),EXTIinit()中NVIC相关的配置配置好
2.添加中断函数TIM2_IRQHandler(),TIM3_IRQHandler(),EXTI15_10_IRQHandler()
3.根据当前主频和所需的波特率，配置执行VirtualCOM_Init(SYSCLK_FREQ_36M,BAUDRATE_9600)初始化函数，
然后就可以从定时器中断中获取接收到的数据，以及使用VirtualCOM_StringSend("abc\r\n")发送数据

备注：此方案用了3个定时器，其中TIM2的作为仅是做延迟，完全可以用COM_RX_Start_Delay(n)取合适的值代替，省一个定时器
***********************************************/
unsigned char g_ucRecvStat = COM_STOP_BIT; 
unsigned char g_ucRecvData = 0;
unsigned char g_iDelayCt=26;//当定时器配置最小时间为5us时，g_iDelayCt固定取26
int iPrescaler =0;
int iPeriod = 0;
unsigned char iPeriodFix = 14;
int g_iCOMRXDelayCt = 0;
/************************************
TIM_Delay_us
*************************************/
int g_iTIM_DelayUs_ct=0;
void TIM_Delay_us(int timeus)//
{
	g_iTIM_DelayUs_ct = timeus;
	TIM_Cmd(TIM2,ENABLE);
	while(g_iTIM_DelayUs_ct>0);
	TIM_Cmd(TIM2,DISABLE);
}

/************************************
配置定时器中断参数
*************************************/
void TIM_TX_Configuration()
{
	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
//	NVIC_InitTypeDef NVIC_InitStructure;//定时器中断向量配置已放在MY_NVIC_Init()中
//	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);  		
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
  TIM_DeInit(TIM2);
  TIM_InternalClockConfig(TIM2);
  TIM_TimeBaseStructure.TIM_Prescaler = iPrescaler - 1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = iPeriod - 1;
  TIM_TimeBaseInit(TIM2,&TIM_TimeBaseStructure);
  TIM_ClearFlag(TIM2, TIM_FLAG_Update);
  TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE);
  TIM_Cmd(TIM2,DISABLE);
	
//  NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
//	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;	
//  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
//  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
//  NVIC_Init(&NVIC_InitStructure);		
}

void TIM_RX_Configuration()
{
	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
//	NVIC_InitTypeDef NVIC_InitStructure;//定时器中断向量配置已放在MY_NVIC_Init()中
//	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);  	
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
  TIM_DeInit(TIM3);
  TIM_InternalClockConfig(TIM3);
  TIM_TimeBaseStructure.TIM_Prescaler = iPrescaler - 1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = iPeriod*g_iDelayCt + iPeriodFix;
  TIM_TimeBaseInit(TIM3,&TIM_TimeBaseStructure);
  TIM_ClearFlag(TIM3, TIM_FLAG_Update);
  TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE);
  TIM_Cmd(TIM3,DISABLE);
	
//  NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
//	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;	
//  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
//  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
//  NVIC_Init(&NVIC_InitStructure);	
}

void TIM_IDLE_TD_Configuration()//空闲保存数据定时器中断
{
	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
//	NVIC_InitTypeDef NVIC_InitStructure;//定时器中断向量配置已放在MY_NVIC_Init()中
//	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);  	
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
  TIM_DeInit(TIM4);
  TIM_InternalClockConfig(TIM4);
  TIM_TimeBaseStructure.TIM_Prescaler = iPrescaler - 1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = iPeriod*g_iDelayCt*10 - 1;
  TIM_TimeBaseInit(TIM4,&TIM_TimeBaseStructure);
  TIM_ClearFlag(TIM4, TIM_FLAG_Update);
  TIM_ITConfig(TIM4,TIM_IT_Update,ENABLE);
  TIM_Cmd(TIM4,DISABLE);
	
//  NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;
//	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;	
//  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
//  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
//  NVIC_Init(&NVIC_InitStructure);	
}
/************************************
配置外部中断
*************************************/
void EXTIinit(void)
{
	GPIO_InitTypeDef GPIO_InitStructure; 
	EXTI_InitTypeDef EXTI_InitStructure;
//	NVIC_InitTypeDef NVIC_InitStructure;//外部中断向量配置已放在MY_NVIC_Init()中
//	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);    
	RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO , ENABLE); 
	GPIO_InitStructure.GPIO_Pin = COM_RX_PIN; 
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; 
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; 
	GPIO_Init(COM_RX_PORT, &GPIO_InitStructure); 

	GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource13); 
	EXTI_InitStructure.EXTI_Line = EXTI_Line13;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt; 
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; 
	EXTI_InitStructure.EXTI_LineCmd = ENABLE; 
	EXTI_Init(&EXTI_InitStructure);  	
	
//外部中断
//  NVIC_InitStructure.NVIC_IRQChannel=EXTI15_10_IRQn;
//  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
//  NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
//  NVIC_Init(&NVIC_InitStructure);	
}

/************************************
配置串口IO
*************************************/
void VirtualCOM_IOconfig()
{
	GPIO_InitTypeDef GPIO_InitStructure;
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
	GPIO_PinRemapConfig(GPIO_Remap_SWJ_Disable, ENABLE); 
	
	GPIO_InitStructure.GPIO_Pin = (COM_TX_PIN); 
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;  
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;  
	GPIO_Init(COM_TX_PORT, &GPIO_InitStructure); 
	GPIO_SetBits(COM_TX_PORT, COM_TX_PIN);
	
//	GPIO_InitStructure.GPIO_Pin = (COM_RX_PIN); //在EXTIinit()中配置
//	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;  
//	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;  
//	GPIO_Init(COM_RX_PORT, &GPIO_InitStructure);   	
}

/************************************
初始化模拟串口
*************************************/
void VirtualCOM_Init(SYSCLK_FREQ SysclkFreq,BAUDRATE BaudRate)
{
  switch (SysclkFreq)
  {
    case (SYSCLK_FREQ_72M): 
			if(BaudRate == BAUDRATE_9600) {iPrescaler=24;iPeriod=12;g_iCOMRXDelayCt=150;}
			if(BaudRate == BAUDRATE_4800)	{iPrescaler=48;iPeriod=12;g_iCOMRXDelayCt=300;}
			if(BaudRate == BAUDRATE_2400)	{iPrescaler=96;iPeriod=12;g_iCOMRXDelayCt=600;}
			if(BaudRate == BAUDRATE_1200)	{iPrescaler=192;iPeriod=12;g_iCOMRXDelayCt=1200;}
      break;
    case (SYSCLK_FREQ_48M): 
			if(BaudRate == BAUDRATE_9600) {iPrescaler=16;iPeriod=12;g_iCOMRXDelayCt=110;}
			if(BaudRate == BAUDRATE_4800)	{iPrescaler=32;iPeriod=12;g_iCOMRXDelayCt=220;}
			if(BaudRate == BAUDRATE_2400)	{iPrescaler=64;iPeriod=12;g_iCOMRXDelayCt=440;}
			if(BaudRate == BAUDRATE_1200)	{iPrescaler=128;iPeriod=12;g_iCOMRXDelayCt=880;}			
      break;
    case (SYSCLK_FREQ_36M): 		
			if(BaudRate == BAUDRATE_9600) {iPrescaler=12;iPeriod=12;g_iCOMRXDelayCt=80;}
			if(BaudRate == BAUDRATE_4800)	{iPrescaler=24;iPeriod=12;g_iCOMRXDelayCt=160;}
			if(BaudRate == BAUDRATE_2400)	{iPrescaler=48;iPeriod=12;g_iCOMRXDelayCt=320;}
			if(BaudRate == BAUDRATE_1200)	{iPrescaler=96;iPeriod=12;g_iCOMRXDelayCt=640;}					
      break;		
	}
	VirtualCOM_IOconfig();
	TIM_TX_Configuration();
	TIM_RX_Configuration();
	TIM_IDLE_TD_Configuration();
	EXTIinit();
}
/************************************
VirtualCOM_ByteSend
发送一个字节
*************************************/
void VirtualCOM_ByteSend(unsigned char val)
{
	u8 i = 0;
	COM_DATA_LOW(); 
	TIM_Delay_us(g_iDelayCt);
	for(i = 0; i < 8; i++) 
	{
		if(val & 0x01)
			COM_DATA_HIGH();
		else
			COM_DATA_LOW();
		TIM_Delay_us(g_iDelayCt);
		val >>= 1;
	}
	COM_DATA_HIGH();
	TIM_Delay_us(g_iDelayCt);
}
/************************************
VirtualCOM_StringSend
发送字符串
*************************************/	
void VirtualCOM_StringSend(u8 *str)
{
	while(*str != 0)
	{
		VirtualCOM_ByteSend(*str);
		str++;
	}
}
/************************************
COM_RX_Start_Delay
接收启动定时器延迟函数
*************************************/	
void COM_RX_Start_Delay(int ct)
{
	while(ct-->0){
		__nop();__nop();__nop();__nop();__nop();__nop();__nop();__nop();
		__nop();__nop();__nop();__nop();__nop();__nop();__nop();__nop();
		__nop();__nop();__nop();__nop();__nop();
	}
}

/**************************************************
以下是中断代码
***************************************************

unsigned char g_ucRX_START=0; 
unsigned char g_ucRX_STOP=0; 
char RecvBuf[1024];
int RecvBufCt=0;

void TIM2_IRQHandler(void)
{
	if(TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET){
		g_iTIM_DelayUs_ct--;
		if(g_iTIM_DelayUs_ct<=0)TIM_Cmd(TIM2,DISABLE);
		TIM_ClearITPendingBit(TIM2,TIM_FLAG_Update);
	}
}

void TIM3_IRQHandler(void)
{
	if(TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET){
		g_ucRecvStat++;
		if(g_ucRecvStat == COM_STOP_BIT){
			TIM_Cmd(TIM3, DISABLE);
			TIM_ClearITPendingBit(TIM3,TIM_FLAG_Update);
			RecvBuf[RecvBufCt]=g_ucRecvData;
			RecvBufCt++;
			g_ucRX_STOP=1;
			TIM_Cmd(TIM4,ENABLE);
			return;
		}
		if(COM_RX_STAT){ //'1'
			g_ucRecvData |= (1 << (g_ucRecvStat - 1));
		}
		else{ //'0'
			g_ucRecvData &= ~(1 <<(g_ucRecvStat - 1));
		}
		TIM_ClearITPendingBit(TIM3,TIM_FLAG_Update);
	}
}

void TIM4_IRQHandler(void)
{
	if(TIM_GetITStatus(TIM4, TIM_IT_Update) != RESET){

		if(g_ucRX_START==1 && g_ucRX_STOP==1){
			g_ucRX_START=0;
			g_ucRX_STOP=0;
//			printf("%s\r\n",RecvBuf);//此处RecvBuf已接收完整，可以取出
			RecvBufCt=0;
			memset(RecvBuf,0,sizeof(RecvBuf));
			TIM_Cmd(TIM4,DISABLE);
		}
		TIM_ClearITPendingBit(TIM4,TIM_FLAG_Update);
	}
}

void EXTI15_10_IRQHandler(void)
{
	if(EXTI_GetITStatus(EXTI_Line13)!=RESET)
	{
		if(!COM_RX_STAT) 
		{
			if(g_ucRecvStat == COM_STOP_BIT) 
			{
				g_ucRecvStat = COM_START_BIT; 
				COM_RX_Start_Delay(g_iCOMRXDelayCt);
				TIM_Cmd(TIM3, ENABLE); 
				g_ucRX_START=1;
				g_ucRX_STOP=0;
				TIM_Cmd(TIM4,DISABLE);
			}
		}
		EXTI_ClearITPendingBit(EXTI_Line13);
	}
}
***************************************************
end
***************************************************/