Counter with pic, in CCS C Compilers

[Amanda Lima264]

Hello, I'm trying to make a control code and I can't, the count works as expected without delay_ms (3000); but when I put it on, the count is much higher, would there be another way to pause without using this delay? I want a pause to turn on and a pause to turn off, without this disturbing the time count, I'm using the ccs c compiler. Thank you in advance.

 while(TRUE)
   {
    if (conta >= 3600 )
    {
      conta = 0;
      minuto++;
    }
      
       delay_ms (3000);   
    
       if(input(!PIN_A3))
      {
       output_low(pin_a0);
       output_low(pin_a1);               
       conta = 0;                   
       minuto=0;
       }
        
           delay_ms (3000);               
      
      if(( minuto <= 10  ) && (input(PIN_A3)))
     {
      output_high(pin_a0); 
      output_high(pin_a1); 
     }
      
   if( minuto > 10)
     {
      output_low(pin_ao);
      output_low(pin_a1);             
      conta = 0;                   
      minuto=0;
      }
      }
      }

 

[andre_luis]

would there be another way to pause without using this delay?

You should consider using Timer interrupt approach, triggering 1 second in your case.
Have a look on CCSinfo compiler manual, page 80 and this example.

 

[FvM]

Would be a good idea to sketch intended timing. I don't recognize how it's time couting, variable conta is nowhere increased in the shown code.

Timer interrupts are a solution, but not the only one. You must get rid of a linear code structure with delays stopping operation. Loop must not necessarily be stopped to execute a delay. It can be also implemented as branch controlled by a delay counter.

 

[Amanda Lima264]

I used it that way too and it didn't work. Remembering that I receive this count from the 60 Hz network in _RA2.

int16 minuto = 0;
int16 conta = 0;
int second = 0;
int LG = 0;
#use delay (clock=4000000)


#INT_RA                             
//------------------------------------------------------------------------
void RA_isr(void)                       
{
  clear_interrupt(INT_RA2);
  if(input(PIN_A2))                 
  {
   conta++;
   LG++;
  }
}

void main()
{
  
     set_tris_a  (0b0001100 ); 
     enable_interrupts(GLOBAL);           
     enable_interrupts(INT_RA2);
     clear_interrupt(INT_RA2);       
     output_low(pin_a0);
     output_low(pin_a1);
 
 while(TRUE)
   {
    if (conta >= 3600 )  // a minute passed
    {
      conta = 0;
      minuto++;
    }
 if (LG >= 60 )  //  a seconds passed
    {
    LG=0;
    second++;
    
    }
    
      ///////////// delay_ms (3000); 
  
       if((input(!PIN_A3)) && (second==3))
      {
       output_low(pin_a0);
       output_low(pin_a1);             
       conta = 0;                 
       minuto=0;
       second=0;
       LG = 0;
       }
      
   /////delay_ms (3000);             
    
      if(( minuto <= 10  ) && (input(PIN_A3)) && (second==3)))
     {
      output_high(pin_a0);
      output_high(pin_a1);
     }
    
   if( minuto > 10)
     {
      output_low(pin_ao);
      output_low(pin_a1);           
      conta = 0;                 
      minuto=0;
     second=o;
     LG = 0;
      }
      }
      }

 

[KlausST]

Hi,

since "conta" is updated within the ISR the variable needs to be declared as "volatile".

And IF the update rate of conta is 1s as recommended ... then 1 minute equals 60 ticks, not 3600 as you wrote.

Klaus

 

[Amanda Lima264]

PIN_A2 receives the positive signal from the electrical network, 60hz, 60 cycles equal to 1 second, 3600 cycles equal to 1 minute.

 

[andre_luis]

You added the routine to deal with I/O interrupt (the counting), but still is missing the routine to deal with Timer interrupt (the time base).

 

[KlausST]

PIN_A2 receives the positive signal from the electrical network, 60hz, 60 cycles equal to 1 second, 3600 cycles equal to 1 minute.

the recommendation was to generate a 1s timer interrupt ...

You did not follow this recommendation. Then probably it will still not work.

Klaus