Display Multiplex Driving with microcontroller (PICMicro) using interrupts and some tweaks....

displays.c

/* Julio Alexander Aguilar Angulo.  25 Juillet 2015
* Created:   jeu. juil. 23 2015
* Processor: PIC16F648A - Compiler:  MPLAB XC8*/

#include <xc.h>
#include <stdint.h>
#include <pic16f648a.h>
// fuse configuration
#pragma config CP=OFF, CPD=OFF, BOREN=OFF, WDTE=OFF//SWDTEN
#pragma config PWRTE=ON, FOSC=INTOSCIO, MCLRE=OFF
#pragma config  LVP=OFF//ON PLLEN=ON,BORV=LO,,  WRT=OFF
// diverse compiler's parameters
#define _XTAL_FREQ 4000000 // 4MHz
#define FOSC 4000000 // 4MHz
// 7 segments  =   gfedcba
uint8_t segs[]={0b0111111,0b0000110,0b1011011,0b1001111,0b1100110,0b1101101,0b1111101,0b0000111, 0b1111111,0b1101111};
uint8_t sels[]={0b1000,0b100,0b10,0b01};
uint16_t par[]={1,10,100,1000};
uint8_t buffer_mcdu[]={0,0,0,0};
uint8_t i,j;
uint8_t it;
uint16_t counter;
//----------------------------------------
void Config_GPIOs(void);
void Delay1(void);
void Convert(uint16_t counter);
void interrupt TIM0int(void);
void ConfigInterrupts(void);
//----------------------------------------
// Interrupt Handler
void interrupt TIM0int(void)
{
  if (INTCONbits.TMR0IF ==1) // timer 0 interrupt flag
  {
    INTCONbits.TMR0IF = 0;         // clear the flag
    INTCONbits.TMR0IE = 1;         // reenable the interrupt
    TMR0 = 6;           // reset the timer preset count
    PORTB=0x00;
    PORTB=segs[buffer_mcdu[i]];
    PORTA=~sels[i];
    i++;
    if (i==4)
    {	i=0;
      	j++;
      	if (j==50)
      	{
	 	j=0;
         	counter++;
         	Convert(counter);
      	} 
    }
  }
}
//---------------------------------------------------
void main()
 {
    Config_GPIOs();
    ConfigInterrupts();
    i=0;j=0; counter=0;
    while (1)  { }
 }
//--------------------------
void Config_GPIOs(void)
 {
    CMCON=0x07;//analog off
    TRISA=0;
    TRISB=0;
    PORTA=0x00;
    PORTB=0x00; }
 
void Delay1(void)
{ uint16_t tmp;
  tmp=800;
  while (tmp>0){tmp--;} 
   }    

void Convert(uint16_t Val)
{
   uint16_t Valt,part;
   Valt=Val;
   for(it=3;it>0;it--)
   {   	part=par[it];  	buffer_mcdu[it]=Valt/part;Valt %=part;}   
   buffer_mcdu[0]=Valt;
}
void ConfigInterrupts(void)
{
OPTION_REGbits.T0CS = 0;  // bit 5  TMR0 Clock Source Select bit...0 = Internal Clock (CLKO) 1 = Transition on T0CKI pin
OPTION_REGbits.T0SE = 0;  // bit 4 TMR0 Source Edge Select bit 0 = low/high 1 = high/low
OPTION_REGbits.PSA = 0;   // bit 3  Prescaler Assignment bit...0 = Prescaler is assigned to the Timer0
OPTION_REGbits.PS2 = 0;   // bits 2-0  PS2:PS0: Prescaler Rate Select bits
OPTION_REGbits.PS1 = 1;
OPTION_REGbits.PS0 = 0;
TMR0 = 6;             // preset for timer register
// Interrupt Registers
  INTCON = 0;           // clear the interrpt control register
  INTCONbits.TMR0IE = 1;        // bit5 TMR0 Overflow Interrupt Enable bit...1 = Enables the TMR0 interrupt
  INTCONbits.TMR0IF = 0;        // bit2 clear timer 0 interrupt flag
  INTCONbits.GIE = 1;           // bit7 global interrupt enable
}