ir.c

基本STC4052写的一个小的OS, 完成了任务调度功能,及堆栈空间切换, 及中断处理

//---------------------------------------------------------------
//      
//       Copyright (c) 2006-2007 E-compass electronic Co.,Ltd.               
//       All Right Reserved.                                     
//                                                               
//       $Author    walnutcy
//       $Email     [e-mail]              
//       $Version   v1.0  
//       $FileName                                       
//       $Since                                            
//       $Log                                                    
//                                                               
//       DESCRIPTION   
//
//		 History:         
//		 <author>          <time>     <version >    <desc> 
//---------------------------------------------------------------
#include "..\includes.h"
#include "IRTable.h"

////////////// global varible ///////////////////////////////////////

IU8 gu8IRBuf[4];
IU8 gu8IRData;
U8 gu8IRState;


S8 lIrBitCnt;
U16 lIrOldCnt ;
S8 lIrFirst;
U16 lIrSubTime;// the counter between the drop impulses
U16 lIrNewCnt;


#define IR_USER_CODE_0  0x10
#define IR_USER_CODE_1  0x67 
////////////////////////////////////////////////////////////////////

/////////////////////////////////////////////////////////////////////


//////////////////////////////////////////////////////


////////////////////////////////////////////////////////////////////////////
static U8 IR_FindIR(U8 cmd) REENTRANT
{
	U8 i = 0;
	while ((cmd != gIRTable[i])&&(40 > i))
	{
		i++;
	}
	if (40 <= i)
	{
		return 0;
	}
	return (i + 1);
}

/////////////////////////////////////////////////////////////////////////////
U8 IR_GetRevData(U8* buf) REENTRANT// get received data
{
	U8 tmp = gu8IRState;
	if(gu8IRState)
	{
        gu8IRState = IR_INVALID;
		*(buf+2) = tmp;
		tmp = IR_FindIR(gu8IRData);
		if (0 != tmp)
        {
            *(buf+0) = tmp;
    		*(buf+1) = ~tmp;
    		return 3;
        }
	}
	return (0);
}


void IR_Init() REENTRANT //initialize system interrupt
{
   	gu8IRState = IR_INVALID;//IR_VALID;//
    gu8IRData = 0xFF;
	lIrBitCnt = 0;
	lIrOldCnt = 0;
	lIrFirst = 1;

    CCON = 0x00;
    CL   = 0x00;
    CH   = 0x00;
    CMOD = 0x00;// enable interrupt
	CCAPM0 = 0x49; // pwm 0 : 16-bit timer(1ms)
    CCAPM1 = 0x11; // pwm 1 : falling edge trigger; IR 
	CCAP0L = SYS_TIME_TICK & 0xff;
    CCAP0H = SYS_TIME_TICK >> 8;
	CR = 1; // start PCA timer
    return;
}  

#if 0
// get the timer value of the triggering by the falling edge of the IR from the remoter
static U16 IR_GetCurrTime() 
{
    U16 l_count ; 

	l_count = CCAP1H;
    l_count = (l_count << 8) + CCAP1L;

	return l_count;
}
#endif

void IR_Decode() REENTRANT
{
    U8 temp;//used as a temp bit value for the received data

//    lIrNewCnt  = IR_GetCurrTime();//the counter value
	lIrNewCnt = CCAP1H;
	lIrNewCnt = (lIrNewCnt<<8) + CCAP1L;
    lIrSubTime = lIrNewCnt - lIrOldCnt;
    lIrOldCnt = lIrNewCnt; 

	if (lIrFirst)
	{
		lIrFirst = 0;
		return;
	}
    // deal with the lIrSubTime
    if ( (NUM0_MIN < lIrSubTime)&&(lIrSubTime < NUM0_MAX) )// 0
    {
        temp = 0;
    }
    else if ( (NUM1_MIN < lIrSubTime)&&(lIrSubTime < NUM1_MAX) )// 1
    {
        temp = 1;
    }
    else if ( (LEAD_MIN < lIrSubTime)&&(lIrSubTime < LEAD_MAX) )// leader code
    {
        gu8IRBuf[0] = 0;
		gu8IRBuf[1] = 0;
        gu8IRBuf[2] = 0;
        gu8IRBuf[3] = 0;
		gu8IRData = 0xFF;
        lIrBitCnt = 0;  
        return;
    }
    else if ( (KEEP_MIN < lIrSubTime)&&(lIrSubTime < KEEP_MAX) )// keep depressed
    {
        gu8IRState = IR_KEEP_DEPRESSED;
		OsSendMsg(TASK_IR);
        return;
    }
    else// interference
    {
        //  do nothing
        return;
    }
	
    /*	deal with the temp value	*/	
	if (31 > lIrBitCnt)
	{
	    gu8IRBuf[lIrBitCnt >> 3] |= temp << (7 - (lIrBitCnt & 0x07));
	}	
    else if ( 31 == lIrBitCnt)// received the last bit 
    {
        gu8IRBuf[3] |= temp;
        // the relation of the invert of data code and the data code 
        //  \data ^ data == 0xff (??)            
        temp =  ~ gu8IRBuf[3];
        if ( gu8IRBuf[2] == temp )
        {   
            if ((IR_USER_CODE_0 == gu8IRBuf[0])&&
                (IR_USER_CODE_1 == gu8IRBuf[1]))
            {
                gu8IRState  = IR_VALID;	
                gu8IRData = gu8IRBuf[2];
				OsSendMsg(TASK_IR);
            }
			else
			{	gu8IRData = 0xFF;
			}
        }
		lIrFirst = 1;
    }
    lIrBitCnt++;
    return;    
}