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By a.mlw.walker
#47710
Hi everyone, I have made a function that does the follwing
1. Wait until button 1 pressed
2. When button 1 pressed start timing
3. Wait until button 1 pressed again
4. When B1 pressed again, record time between B1 press 1 and B1 press2
5.Continue timing
6, When B1 pressed again record time bewteen B1 press 2 and B1 press 3

Its so that I can calculate the acceleration of an object, the code is below that does this. But i think it could be more accurate with interupts, could anyone show me how it would be done more accurately?

Thanks
Code: Select all
int timing()
{
while (PINC&(1<<PC5))  // loop here until first button press
  ;

  _delay_ms(10);  // delay for 10 ms to debounce the press
  
while (!(PINC&(1<<PC5)))  // loop here until button is released
   ;
  _delay_ms(10);  // delay for 10 ms to debounce button release

  time_ms1 = 0;  // here is where we start timing
  time_ms2 = 0;
  TCNT1 = 0;

  while (PINC&(1<<PC5))  // loop here until second button press
  {

   // while waiting for button press, keep track of elapsed time
   //  if system clock is 1 MHz, 1000 TCNT1 ticks = 1 ms
   //  if system clock is 8 MHz, 8000 TCNT1 ticks = 1 ms
   if (TCNT1 >= 1000)
   {
     time_ms1++;
     TCNT1 = 10;
   }
  }
  
  while (!(PINC&(1<<PC5)))  // loop here until button is released
   ;
  _delay_ms(10);  // delay for 10 ms to debounce button release
  

  TCNT1 = 10;
while (PINC&(1<<PC5))  // loop here until 3rd button press
  {

   // while waiting for button press, keep track of elapsed time
   //  if system clock is 1 MHz, 1000 TCNT1 ticks = 1 ms
   //  if system clock is 8 MHz, 8000 TCNT1 ticks = 1 ms
   if (TCNT1 >= 1000)
   {
     time_ms2++;
     TCNT1 = 10;
   }
  }
   lcd_line1();// display the times
  lcd_time(time_ms1);
  lcd_line2();
  lcd_time(time_ms2);  
  
  }
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