realtime.c

MANTIS是由科罗拉多大学开发的传感器网络嵌入式操作系统。 这是mantis的0.9.5版本的源码。

//  This file is part of MANTIS OS, Operating System
//  See http://mantis.cs.colorado.edu/
//
//  Copyright (C) 2003,2004,2005 University of Colorado, Boulder
//
//  This program is free software; you can redistribute it and/or
//  modify it under the terms of the mos license (see file LICENSE)


#include "mos.h"

#include "msched.h"
#include "led.h"

#ifndef SCONS
#include "config.h"
#endif

/** @brief Local Variables for measuring time elapsed
 *
 */
static uint32_t realtime_count;
static uint16_t skew_adjust;

void real_timer_clear()
{
   realtime_count=0;
   TCNT2 = 0;
}

void real_timer_init(void)
{
   skew_adjust=1;
   uint8_t int_handle;
   int_handle = mos_disable_ints();
   TCCR2 &= ~((1 << WGM20));
   TCCR2 |= (1 << WGM21);//Clear timer after interrupt
   TCCR2 |= (1 << CS21) | (1 << CS20);
   OCR2   = 114;          //fire an interrupt every ms
   TIFR  |= (1 << OCF2);  //clear flag
   TIMSK |= (1 << OCIE2); //turn on interrupt
   real_timer_clear();
   mos_enable_ints(int_handle);
}

inline uint32_t* real_timer_get_ticks()
{
   return &realtime_count;
}

SIGNAL(SIG_OUTPUT_COMPARE2)
{
/*
   realtime_count++;
   if((skew_adjust++ % 160) == 0){
      realtime_count++;
      skew_adjust = 1;
   }
*/
}