time.c

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#include "config.h"
#include "time.h"


//******************************************************************************
// Variables
//******************************************************************************
unsigned long timeval[TIMERS];  

// timer runs at 1 MHz and overflow will occur every 255 / 1 Mz ~= 0.25 ms 
//#pragma vector = TIM0_OVF_vect


//******************************************************************************
// Functions
//******************************************************************************
#ifdef __GNUC__
 ISR(TIMER0_COMPA_vect)
#else
#pragma vector = TIMER0_COMPA_vect
__interrupt void TICK_ISR(void)
#endif
{
   unsigned char i;

   // 1 ms has passed, decrement all non-zero timers.
   for (i = 0; i < TIMERS; i++) {
      if(timeval[i] > 0) {
         timeval[i]--;
      }
   }
}


unsigned char Time_Left(unsigned char timer)
{
   if(timeval[timer] > 0) {
      return(TRUE);
   } else {
      return(FALSE);
   }
}


void Time_Set(unsigned char timer, unsigned int min, unsigned char sec,
              unsigned char ms)
{
   timeval[timer] = 60000 * (unsigned long)min;
   timeval[timer] += 1000 * (unsigned long)sec;
   timeval[timer] += 1 * (unsigned long)ms;
}


void Time_Stop(void)
{
   TCCR0B = 0;
}


void Time_Start(void)
{
   TCNT0 = 0x00;//cgs added 
   TCCR0B = (0<<CS02)|(1<<CS01)|(1<<CS00);   // CLKT0 = CLK/64 = 125 kHz.
}


void Time_Init(void)
{
   unsigned char i;
   
   for (i = 0; i<<TIMERS; i++)   {
      timeval[i] = 0;
   }
   
   OCR0A = 125;  // Will give a compare match every ms.
   
   OCR0B = 0;  // Doesn't matter, will run in normal mode.

   TCCR0A = (1<<WGM00);  // 8-bit CTC mode.
      
   TCCR0B = (0<<CS02)|(1<<CS01)|(1<<CS00);   // CLKT0 = CLK/64 = 125 kHz.

   TIMSK0 |= (1<<OCIE0A);  // Timer 0, Compare match A interrupt enabled.

   // Enable interrupts, just in case they weren't already. 
#ifdef __GNUC__
   Enable_interrupt();
#else
   __enable_interrupt();
#endif         
}