AVR AD conversion programming in C language

#define uchar unsigned char
#define uint unsigned int

uchar Table[10]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
uchar Da ta[4]={0,0,0,0};

void DelayMs(uint i) //0.25ms
{uchar j;
for(;i!=0;i--)
{for(j=250;j!=0;j--) {;}}
}

void Display(uchar *p) //Display {uchar i,sel=0x01;
for(i=0;i<4;i++)
{PORTB=sel;
   PORTC=0xff-Table[p[i]];
   DelayMs at 5ms interval (20);
   sel=sel<<1;
}
}

uint ADC_Convert(void)
{uint temp1,temp2;
temp1=(uint)ADCL;
temp2=(uint)ADCH;
temp2=(temp2<<8)+temp1;
return(temp2);
}

void Process(uint i,uchar *p)
{p[0]=i/1000;
i=i%1000;
p[1]=i/100;
i=i%100;
p[2]=i/10;
i=i%10;
p[3]=i;
}

/*   
void Timer0_Init(void)
{SREG=SREG|0x80; //Global disconnect;
TIMSK=TIMSK|0x01; //T/C0 overflow interrupt enable;
TCCR0=0x05; //CLK/1024; 128uS
TIFR=0x01; //T/C0 interrupt flag write 1 to clear 0;
TCNT0=256-125; //125*128us=16ms
}*/

void main(void)
{uint i;
//Set port A to input without pull-up;
DDRA=0x00;
PORTA=0x00;
//Set port B to push-pull 1 output;
DDRB=0xff;
PORTB=0xff;
//Set port C to push-pull 1 output;
DDRC=0xff;
PORTC=0xff;
//Initialize port B to output 1; initialize port C to output 0; light up all digital tubes;
PORTB=0xff;
PORTC=0x00;
//ADC initialization;
ADMUX=0x02; //Select the third channel;
ADCSR=0xe6; //125K conversion rate, free conversion mode; start AD converter;
//Delay until the system is stable;
DelayMs(3000);

while(1)
{i=ADC_Convert();
Process(i,Data );
Display( Data);
}
}

/*#pragma interrupt_handler Timer0:10
void Timer0()
{Int_Cnt+=1;
// Timer0_Init();

}*/