TIMER0 Interrupt

[emanuellima]

Hello all,

I am developing a project with a PIC18F45K22, and I want to use TIMER interrupts. A sensor will enable an interrupt at pin RB0, and then this interrupt will start the TIMER, when the timer is 1 min a LED should be turned ON.

I am using a internal osc at 16MHz.

Can you help me? how could I do it?

so far I was trying to use the code bellow

Code: Select all

void interrupt(void){

     if(INT0F_bit == 1){
        PORTD.B0  = 1;
        text2 = ("   INTERRUPT   ");

        T0CON.TMR0ON = 1;      //Now start the timer!
        INT0F_bit = 0;
        Delay_ms(500);
        PORTD.B0  = 0;
        //text2 = ("  Temperature:   ");
     }
     else if(T0CON.TMR0IE && T0CON.TMR0IF){
      //TMR0 Overflow ISR
      counter++;  //Increment Over Flow Counter

      if(counter == 61)
      {
         //Toggle RB1 (LED)

         if(PORTD.B5  = 0)
            PORTD.B5 = 1;
         else
            PORTD.B5 = 0;
            
         counter = 0;  //Reset Counter

      }

      //Clear Flag
      T0CON.TMR0IF = 0;
      }

}

and the main menu

Code: Select all

  INTCON.GIE  = 1;                   // Enable GLOBAL interrupts
  INTEDG0_bit = 1;                   // Set interrupt on rising edge
  INT0IE_bit  = 1;                   // Enable INT0 interrupts
  INTCON.PEIE = 1;                   //peripharel interrupt enable
  INTCON.TMR0IF = 0x0; //Clear timer0 overflow interrupt flag
  INTCON.TMR0IE = 1;   //Enable TIMER0 Interrupt
  T0CON.T08BIT = 0;    //8 BIT MODE
  T0CON.T0CS = 0;      //Prescaler gets clock from FCPU (5MHz)
  T0CON.PSA = 0b111;       //Timer Clock Source is from Prescaler

[darko.minic]

Hello,

We provide examples for timer0 interrupt, you can find it in compiler examples folder:
\Mikroelektronika\mikroC PRO for PIC\Examples\Internal MCU modules\P18F45K22\Timer0 Interrupt

Also if you want to use external interrupt you should look at following example for UNI Hall Click:
http://www.libstock.com/projects/downlo ... oc_pic.zip

You should look at this examples and try to implement them in your code.

Regards,
Darko

[jayanthd]

Try attached code. Proteus 8.1 file attached.

Use mikroE Timer Calculator tool.

Code: Select all

unsigned int counter = 0;

//Timer1
sbit LED at LATD0_bit;
sbit LED_Direction at TRISD0_bit;

//Prescaler 1:8; TMR1 Preload = 15536; Actual Interrupt Time : 100 ms

//Place/Copy this part in declaration section
void InitTimer1() {
    T1CON = 0x31;
    TMR1IF_bit = 0;
    TMR1H = 0x3C;
    TMR1L = 0xB0;
    TMR1IE_bit = 1;
}

void Interrupt() {

    if(INT0IF_bit) {
         counter = 0;
         InitTimer1();
         INT0IF_bit = 0;
         INT0IE_bit = 0;
    }

    if(TMR1IF_bit) {
    
         if(++counter == 600) {     //counter value = 600 = 60 sec (100 ms timer Interrupt)
              LED = 1;
              counter = 0;
              TMR1ON_bit = 0;
              INT0IE_bit = 1;
         }
    
        TMR1IF_bit = 0;
        TMR1H         = 0x3C;
        TMR1L         = 0xB0;
        //Enter your code here
    }
}

void main() {

     ANSELA = 0x00;
     ANSELB = 0x00;
     ANSELC = 0x00;
     ANSELD = 0x00;
     ANSELE = 0x00;
     
     CM1CON0 = 0x00;
     CM2CON0 = 0x00;
     
     TRISA = 0xFF;
     TRISB = 0x01;
     TRISC = 0x00;
     TRISD = 0x00;
     TRISE = 0x08;
     
     PORTA = 0x00;
     PORTB = 0x00;
     PORTC = 0x00;
     PORTD = 0x00;
     PORTE = 0x00;
     
     LATA = 0x00;
     LATB = 0x00;
     LATC = 0x00;
     LATD = 0x00;
     LATE = 0x00;
     
     LED_Direction = 0;
     LED = 0;
     
     IRCF0_bit = 1;
     IRCF1_bit = 1;
     IRCF2_bit = 1;
     
     INTEDG0_bit = 1;
     INT0IF_bit = 0;
     INT0IE_bit = 1;
     PEIE_bit = 1;
     GIE_bit = 1;
     
     while(1) {
     
     }
}

[darko.minic]

Hello Jayanth,

Thank you for sharing your knowledge and experience with our users.

Best regards,

[aparna k]

Hi,
I am trying to implement timer0/timer1 interrupt using PIC18F67K40. But it is not working. Can anyone send me the code?

[jovana.medakovic]

Hello,

In the attachment, you can find an example for timer0 and timer1 for PIC18F67K40.

Kind regards,
Jovana