Hello,
I have done 2 digit counter successfully with E2PROm of PIC16F877a in H tech c code.
but i have problem with 3 digit after 99 something like that the middle display get suck and brightness is now also issue.
here is my code and i am scanning it as usual

please suggest if something is wrong in it...

 TRISB = 0X00 ;
    TRISC = 0B00000011 ;
unsigned int a=0;
unsigned int b=0;
unsigned int div;
unsigned int rem;
while(1){
b=eeprom_read(0x00);
PORTC=0b10000000;
rem = a%10;
PORTB=data[rem];
__delay_ms(5);
PORTC=0b01000000;
div=a/10;
PORTB=data[div];
__delay_ms(5);

PORTC=0b00100000;
div=a/100;
PORTB=data[div];
__delay_ms(5);





   
if(RC0==1){
__delay_ms(100);
a=a+1;
// eeprom_write(0x00, a);
if(a>999){
a=999;
}}
  if(RC1==1){
__delay_ms(100);
//eeprom_write(0x00, a);
a=a-1;
if(a>999){
a=0;
}
}
    }
        }

 

Your basic idea is fine but you lost track of it past the units display.
When you do a modulus division by 10 you get the units digit, but the original variable remains unchanged. You would have to do the following:

    PORTC=0b10000000;
    rem = a%10;
    a=a/10;            // add this
    PORTB=data[rem];
    __delay_ms(5);
    PORTC=0b01000000;
    rem=a%10;        // was div
    a=a/10;            // add this
    PORTB=data[rem];    // was div
    __delay_ms(5);
    PORTC=0b00100000;
    // div=a/100;        // will ONLY work when a<1000
    // PORTB=data[div];    // will ONLY work when a<1000
    rem=a%10;        // add this instead
    a=a/10;            // add this instead
    PORTB=data[rem];    // add this instead

 

Hello,

I have updated the code as per your suggestion, but the problem is that the eeprom i think save data 8 bits i.e. 255 only in display so, i need the data should be at 999 how to move above 255 as i increment it it shows 000 please tell how to do this....

#include <htc.h>
#include <stdio.h>
__CONFIG(LVP_OFF& BOREN_OFF & PWRTE_ON & WDTE_OFF & FOSC_HS);
#define _XTAL_FREQ 20000000

char data[13]={  0b01111110,0b00010010,0b10111100,0b10110110,0b11010010,0b11100110,0b11101110, 0b00110010,0XFF,0b11110110};
main()
    {
    TRISB = 0X00 ;
    TRISC = 0B00000011 ;
unsigned int a=0;
unsigned int b=0;
unsigned int div;
unsigned int rem;
while(1){

b=eeprom_read(0x00);

PORTC=0b10000000;
rem = b%10;
b=b/10;
PORTB=data[rem];
__delay_ms(10);
PORTC=0b01000000;
rem=b%10;
b=b/10;
PORTB=data[rem];
__delay_ms(10);

PORTC=0b00100000;
rem=b%10;      
  
PORTB=data[rem];
__delay_ms(10);


if(RC0==1){
__delay_ms(90);
a=a+1;

eeprom_write(0x00, a);

if(a>999){
a=999;
}}

  if(RC1==1){
__delay_ms(90);
eeprom_write(0x00, a);

a=a-1;
if(a>999){
a=0;
}
}
    }
        }

 

working fine for 3 digit pls suggest if u found any thing wrong any suggestion to increase the brightness..??

and how this scanning method implemented..?
http://electronics.stackexchange.co...ightness-of-multiplexed-7-segment-led-display

 

Note the method you link to employs common anode displays with two sub sets of anodes, each connected to four elements. Also, the post concerns the display having a lack of brightness, so it is not a good source of information for making a bright display. Someone does make good points about not driving LEDs directly from port pins without resistors.
No comparison can be made to your work as your work is a mystery without a schematic being posted.