increasing a number into a PIC16f690 via interrupt

[picozero]

Hi
I have a simple problem is driving me crazy:
Let's start "for dummies", just increasing one value of +1 every time I send an input High to RA1:
What 's missing ? Do I need something particular like a timer ? The datasheet is very unclear to me and the example are in assembry (that I don't know).

 #include <htc.h>

 /***** CONFIGURATION *****/
 __CONFIG(MCLREN & UNPROTECT & WDTDIS  & INTIO);
 
 /***** PROTOTYPES *****/
 void set7segC(char digit);           // display digit on 7-segment display
 void set7segAB(char digit);           // display digit on 7-segment display
 
 
 //Global variable, dealt by interrupts
     unsigned int    adc_dec;        // scaled ADC output (0-99)
 
 /***** MAIN PROGRAM *****/
 void main()
 {
     adc_dec = 0; // initialize global value
     
     // configure ports
     TRISA  = 0b11101011;
     ANSEL  = 0b00000001;
     ANSELH = 0b00000001; 
     TRISB  = 0b00000000;                      // configure PORTB and PORTC as all outputs
     TRISC  = 0b00000000;
     CM1CON0 = 0;                    // disable comparator 1 (RB0, RB1, RB2 usable)
     CM2CON0 = 0;                    // disable comparator 2 (RC0, RC1, RC4 usable)
     VRCON   = 0;                      // disable CVref (RC2 usable)
     // configure ADC     
     ADCON0 = 0b10000001;       
              //1------             Right justified
              //-0------            VDD
              //--0000--            Set AN0 as the input !!!!! AN0 = RA0
              //-------00             turn ADC off  
     ADCON1 = 0b00010000; //Before turning on the ADC
 
 //Interrupts setting
 GIE=1;
 INTEDG=1;
 PEIE=1;
 RABIE=1;
 IOCA = 0b00000010; //Enable only RA1
         
     ADON=1;           // turn on the A2D conversion module
     // Main loop
     for (;;)
     {
         // sample input
         GODONE = 1;             // start conversion
         while (GODONE);          // wait until done
         
 /*
         // scale result to 0-99
         //adc_dec =(((ADRESL + (ADRESH << 8)) * 3) / 31);
          if(RA1) // Read the volt value on the input while the redled is on
     {
       red_led =  (((ADRESL + (ADRESH << 8)) * 3) / 31);
     }
         if(RA5)// Read the volt value on the input while the irled is on and update the output
     {
       ir_led =  (((ADRESL + (ADRESH << 8)) * 3) / 31);
       adc_dec = ir_led;//red_led / ir_led;
     }
 */
  
     set7segC(adc_dec%10);    // output ones digit of result on segment bus 
     set7segAB(adc_dec/10);   // output tens digit of result on segment bus 
     }
 
       
 }
 
 //Interrupt Handler
 void interrupt ISR( void ) 
 {
     /* Is this a port change interrupt and is it enabled? */
     if( RABIF && RABIE ) 
     {
         RABIF = 0;
         adc_dec= adc_dec +1;
      }
 }

For some strange reason the number on the segment is not updated, but if I put straightforward

 void interrupt ISR( void ) 
 {
     /* Is this a port change interrupt and is it enabled? */
     if( RABIF && RABIE ) 
     {
         RABIF = 0;
         adc_dec= 5;
      }
 }

THe display will show me 5 .... strange question

 

[3v0]

Use a debugger to step through you code and observe what is going on.

 

[picozero]

Hi!
Thank you for addressing me to the right direction.
I have done the debug using the MPlab simulator.
Something weird happens.
Without stimulus (therefore no interrupt), the code stuck at
set7segC(adc_dec%10); // output ones digit of result on segment bus
set7segAB(adc_dec/10); // output tens digit of result on segment bus
and this is ok!

if I "fire" the stimulus, the code jumps on
void interrupt ISR( void )
and does not go out anymore even if I reset RABIF = 0;
Any suggestions ? Is there anything else I should reset to go out the interrupt and back to the main function ?


Or the problem is the fact the timer is not set ?

 

[picozero]

I solved in this way but it doesn't make any sense:

I put
RABIE= 0;
inside the interrupt function and at this point the function was closing and going back to the main.

Inside the main I reactivate RABIE =1 otherwise the interrupts are not enable.
There must be a more sensible way !!!!