Dear sir,
I have pasted the programe.
And tell me what is the variable for dig_disp. Please make me understand it.
#include<reg51.h>
sbit dig_ctrl_4=P1^0; //Declaring control pins of the seven segments
sbit dig_ctrl_3=P1^1;
sbit dig_ctrl_2=P1^2;
sbit dig_ctrl_1=P1^3;
unsigned char dig_disp=0;
int min2;
int min1;
int sec2;
int sec1;
char digi_val[10]={0x40,0xF9,0x24,0x30,0x19,0x12,0x02,0xF8,0x00,0x10};
void delay() //Function to provide a time delay of approx. 1 second. using Timer 1.
{
int i;
for(i=0;i<20;i++)
{
TL1=0xFD;
TH1=0x4B;
TR1=1;
while(TF1==0);
TR1=0;
TF1=0;
}
}
void display() interrupt 1 //Function to display the number using seven segmnet multiplexing. For more details refer seven segment multiplexing.
{
TL0=0x36; //Reloading Timer0
TH0=0xf6;
P2=0xFF;
dig_ctrl_1 = dig_ctrl_3 = dig_ctrl_2 = dig_ctrl_4 = 0;
dig_disp++;
dig_disp=dig_disp%4;
switch(dig_disp)
{
case 0:
P2=digi_val[sec1];
dig_ctrl_1 = 1;
break;
case 1:
P2= digi_val[sec2];
dig_ctrl_2 = 1;
break;
case 2:
P2= digi_val[min1];
dig_ctrl_3 = 1;
break;
case 3:
P2= digi_val[min2];
dig_ctrl_4 = 1;
break;
}
}
void main()
{
TMOD=0x11; //Intialize Timer 0
TL0=0x36;
TH0=0xF6;
IE=0x82; // Enable Timer 0 interrupt
TR0=1; //Start Timer 0
while(1) //Start clock
{
min2=min1=sec2=sec1=0;
for(min2=0;min2<6;min2++)
{
for(min1=0;min1<10;min1++)
{
for(sec2=0;sec2<6;sec2++)
{
for(sec1=0;sec1<10;sec1++)
{
delay();
}
}
}
}
}
}