systimer.c

实现120无传感器变频输出

/***********************************************************************/
/*                                                                     */
/*  FILE        :systimer.c                                        */
/*  DATE        :Tue, Jun 07, 2005                                     */
/*  DESCRIPTION :Main Program                                          */
/*  CPU TYPE    :Other                                                 */
/*                                                                     */
/*  This file is coded by RSBJ WRD     */
/*                                                                     */
/***********************************************************************/
#define INVALID_TIM		(0x80000000L)

#include "systimer.h"



static TIMEBASE systm = { 0x0L,0x0L};
				  
void sys_timer(void)
{
	if ( systm.tm_lo < 0xffffffff )
	{
		systm.tm_lo ++;
	}
	else
	{
		systm.tm_lo = 0;
		if ( systm.tm_hi < 0x7fffffff )
		{
			systm.tm_hi ++;
		}
		else
		{
			systm.tm_hi = INVALID_TIM;
			systm.tm_lo = 0xffffffff;
		}
	}
}

BOOLEAN get_curtime ( TIMEBASE * const cur_tm )
{
	if ( INVALID_TIM == systm.tm_hi  )
	{
		return (false);
	}
	else
	{
		cur_tm -> tm_lo = systm.tm_lo;
		cur_tm -> tm_hi = systm.tm_hi;
		return (true);
	}
}

UINT_32 time_dif(TIMEBASE * const cur_tm,TIMEBASE *const pre_tm)
{
	
	if ( cur_tm->tm_hi  != pre_tm->tm_hi )
	{
		return (INVALID_TIM);/*unit: 0.1 sec*/
	}
	else
	{ 
		if ( cur_tm->tm_lo < pre_tm->tm_lo)
		{
			return ( INVALID_TIM );/*unit: 0.1 sec*/
		}
		else
		{
			return (cur_tm->tm_lo - pre_tm->tm_lo); /*unit: 0.1 sec*/
		}
	}
	
}