PIC Development Board

/*
* Project name:7SEGMENT DISPLAY
PIC Development Board
* Copyright
(c) Researchdesignlab.com
* Test configuration:
MCU: PIC16F877A
Dev.Board: PIC
Oscillator: 20.0 MHz
Software: MPLAB IDE v8.92(HI-TECH_C)
*/

#include<htc.h>

#define CNTRL_PORT PORTA
#define DATA_PORT PORTB

void hex2dec(unsigned char);
void send_seg(unsigned char,unsigned char,
unsigned char,unsigned char);
void DelayMs(unsigned int);
unsigned char x;
unsigned char thou=0,hun=0,ten=0,single=0;
unsignedcharCA[10] = {0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};
unsignedchar CC[10] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
unsigned char CA_CNTRL[4] = {0x07,0x0b,0x0d,0x0e};
unsigned char CC_CNTRL[4] = {0x08,0x04,0x02,0x01};
unsigned char n=1;
void main()
{
unsigned char number;
nRBPU =0;
TRISB=0x00; //PORTB configured as O/P
ADCON1=0x07; //Configure PORTA & PORTE as Digital port
TRISA=0x00; //PORTA Configured as O/P
while(1)
{
if(x == 200)
{
x=0;
single++; //Increment up to 9 in unit place
if(single>9)
{
single=0;
ten++; //Increment up to 9 in Tenth place
if(ten>9)
{
ten=0;
hun++; //Increment up to 9 in Hundredth place
if(hun>9)
{
hun=0;
thou++; //Increment up to 9 in Thousandth place
if(thou>9)
thou=0;
}
}
}
}
x++;
send_seg(thou,hun,ten,single);
}
}
void send_seg(unsigned char thou,unsigned char hun,unsigned char ten,unsigned char single)
{
if(n==1)
{
CNTRL_PORT=CA_CNTRL[0]; //Eanble Unit place 7-Segment
DATA_PORT=CA[single]; //Display Unit Place Number
n=2;
DelayMs(5);
}

else if(n==2)
{
CNTRL_PORT=CA_CNTRL[1]; //Eanble Tenth place 7-Segment
DATA_PORT=CA[ten]; //Display Tenth Place Number
n=3;
DelayMs(5);
}
else if(n==3)
{
CNTRL_PORT=CA_CNTRL[2]; //Enable Hundredth place 7-Segment
DATA_PORT=CA[hun]; //Display Hundredth Place Number
n=4;
DelayMs(5);
}
else if(n==4)
{
CNTRL_PORT=CA_CNTRL[3];//Eanble Thousandth place 7-Segment
DATA_PORT=CA[thou]; //Display Thousandth Place Number
n=1;
DelayMs(5);
}
}
void DelayMs(unsigned int Ms)
{
int delay_cnst;
while(Ms>0)
{
Ms--;
for(delay_cnst = 0;delay_cnst <220;delay_cnst++);
}
}