os_timer.c

引入事件驱动观念的抢占式多任务微型实时内核——MicroStar的设计与实现；提出基于事件的优先级这一新概念。

/**************** os_timer.c**************/
/*            MacroStar 1.0a            */
/*          Zhengyuquan,2003.7,Beijing  */
/*           All rights reserved        */
/****************************************/
#include "mStar.h"
volatile uint_16 	os_timerState=0XFFFF;
const    uint_16 	os_timerMask=0XFFFF;
		 TIMER    	os_timers[MAX_TIMER_NUM];	// 16*8=128
volatile uint_16 	os_sysTime;

/*
************************************************************
*
*
*
************************************************************
*/
void STDCALL _FAR os_OnTimerIn( )
{
	register uint_16 timerMask = 0x8000;
    uint_16  timerflag =  os_timerState^os_timerMask;
    PTIMER   pTimer    =  os_timers;
	PTCB     pTCB;

	os_sysTime++;
    while( timerflag )
	{
		if(timerMask&timerflag)
		{
			if( !(--pTimer->elapse) )
			{
				pTCB = &os_tcbs[ pTimer->taskId ];
				if( pTimer->lpTimerFunc)(*pTimer->lpTimerFunc)(pTimer->taskId,pTimer->timerId);
				pTimer->elapse = pTimer->backTime;
				switch( pTimer->timerId&0xF0 )
				{
				case SLEEP_ID:
					os_slpState   |= os_maskTable[ pTCB->priority ];
					os_timerState |= timerMask;
					os_SetSwitchFlag( );
					break;
				case 0x00:
					pTCB->msg[0] |= os_maskTable[ pTimer->timerId ];
					os_rdyhState |= os_maskTable[ pTCB->priority ];
					os_SetSwitchFlag( );
					break;
				case 0x10:
					pTCB->msg[1] |= os_maskTable[pTimer->timerId&0x0f];
					os_rdyState |= os_maskTable[ pTCB->priority];
					os_SetSwitchFlag( );
					/*default*/
				}
			}
			timerflag ^= timerMask;
		}
		pTimer++;
		timerMask >>= 1;
	}
}

/*
************************************************************
*
*
*
************************************************************
*/
HTIMER STDCALL _FAR os_SetTimerIn(uchar timerId, uint_16 elapse, TIMERPROC lpTimerFunc)
{
	HTIMER hTimer = NULL_TIMER;
	PTIMER pTimer;
    uint_16 temp ;
    
	ENTER_CRITICAL_SEG( );
	if( temp = os_timerState )
    {
		if(HIGHBYTE(temp))
			hTimer = os_fastTable[ HIGHBYTE(temp) ];
		else
			hTimer = os_fastTable[ LOWBYTE(temp) ] | 8;

		pTimer = &os_timers[hTimer];
		pTimer->backTime = elapse;
		pTimer->timerId = timerId;
	    pTimer->taskId  = os_GetCurrentTaskId( );
		pTimer->lpTimerFunc = lpTimerFunc;

		LOCK_INT( );
		os_timerState ^= os_maskTable[ hTimer];
		pTimer->elapse = elapse;
		UNLOCK_INT( );
	}
	LEAVE_CRITICAL_SEG( );

	return hTimer;
}

/*
************************************************************
*
*
*
************************************************************
*/
void STDCALL _FAR os_KillTimer(HTIMER hTimer)
{
	os_ASSERT( !(hTimer&0xF0),KILL_INVALID_HTIMER );
	os_WARNING( !(os_timerState&os_maskTable[hTimer]),KILL_UNUSED_TIMER);
	os_timerState |= os_maskTable[ hTimer ];
}

/*
************************************************************
*
*
*
************************************************************
*/
void STDCALL _FAR os_Sleep(uint_16 elapse)
{
	LOCK_SCHEDULE( );

	if( os_timerState )
    {
		os_slpState ^= os_curPrioMask;
 	    os_SetTimerIn(SLEEP_ID,elapse,0);
	}
	UNLOCK_SCHEDULE( );
    os_Schedule( );
}


#ifdef _DEBUG
/*
************************************************************
*
*
*
************************************************************
*/
HTIMER STDCALL _FAR os_SetTimer(uchar timerId, uint_16 elapse, TIMERPROC lpTimerFunc)
{
	os_ASSERT( !(timerId&0xC0),SET_INVALID_TIMERID);
	return os_SetTimerIn(timerId,elapse,lpTimerFunc);
}

#endif