#include <reg51.h>
sbit rs=P3^0;
sbit rw=P3^1;
sbit en= P3^2;
sbit  sw0= P3^3;
sbit  sw1= P3^4;
sbit  led0= P3^5;
sbit  led1= P3^6;
sbit  led2= P3^7;

void msdelay(void);
void delay(unsigned int);
void cmd(unsigned char);
void dat(unsigned char);

void main(void)
{
	unsigned int number[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};
	unsigned char ch[]="room is full";
	unsigned char ch1[]="keep entering";
	unsigned char ch2[] ="ROOM IS EMPTY";
	unsigned int k,s;
	P1=0xC0;
	 while(1){
 if (sw0==0 && s<9)	 
 { 
     s++;
	   cmd(0x01);
	   P1= number[s];
	   msdelay ();
	   if (s==9)
			 {
	   cmd(0x80);
	   cmd(0x0c);
	   cmd(0x06);
			for(k=0;ch[k]!='\0';k++)
	   dat(ch[k]);
		 led0=0;
		 led1=1;
		 led2=1;			 
		}
		else
		{
	   cmd(0x80);
	   cmd(0x0c);
	   cmd(0x06);
			for(k=0;ch1[k]!='\0';k++)
	   dat(ch1[k]);
	  led1=0;	
    led0=1;
    led2=1;	
		}
 }
 else if(sw1==0 && s>0)
 {
	 s--;
	 cmd(0x01);
	 P1 = number[s];
	 msdelay (); 
	   if (s==0){
	   cmd(0x80);
	   cmd(0x0c);
	   cmd(0x06);
			for(k=0;ch2[k]!='\0';k++)
	   dat(ch2[k]);
			led0=1;
			led1=1;			 			 
	  	led2=0;
		}
		else 
		{	
	    cmd(0x80);
	   cmd(0x0c);
	   cmd(0x06);
			for(k=0;ch1[k]!='\0';k++)
	   dat(ch1[k]);
			led0=1;
			led1=0;
			led2=1;
		}
  }
 else if (s==0)
 {
	   cmd(0x80);
	   cmd(0x0c);
	   cmd(0x06);
			for(k=0;ch2[k]!='\0';k++)
	   dat(ch2[k]);
			led0=1;
			led1=1;
	    led2=0;
   }
 }
}
void delay(unsigned int t)
{
	unsigned int i,j;
	en=1;
	for(i=0;i<t;i++)
	for(j=0;j<150;j++);
	en=0;
}
void msdelay()
{
	unsigned  int a,b;
 for(a = 0; a <50; a++)
	{
    for(b = 0; b <50; b++)
		;
	}
}
void cmd(unsigned char ch)
{
    
	rs=0;
	rw=0;
	P2=ch;
	delay(20);
}
void dat(unsigned char ch)
{
	
	rs=1;
	rw=0;
	P2=ch;
	delay(20);
}