#pragma SMALL DB OE
#include <reg51.h>

sbit power = P0^0;
sbit green = P0^1;
sbit red = P0^3;


char ReceiveSerial() {

        char c;
        TMOD = 0x20;    /* configure timer for the correct baud rate */
        TH1 = 0xe6;     /* 1200 bps for 12 MHz clock */
        TCON = 0x00;    /* Set timer to not running */
        SCON = 0x50;    /* Set Serial IO to receive and normal mode */
        TR1 = 1;        /* start timer to Receive */

        while( (SCON & 0x01) == 0 ) /* wait for receive data */;
        c = SBUF;

        return c;
}                   

/* Delay function */

void delay() {
int i, j;

     for (i=0; i<1000; i++)
          for (j=0; j<50; j++)
		i=i+0;
}

/* Main function which will blink LED */

void main (void) {
   char c;

   power = 0;  /* on */
   red = 0;    /* off */
   green = 0;  /* off */

   while(1)  {
     c = ReceiveSerial();
     if (c == 'x')            /* closed */
        {
	    red = 0;
	    green = 1;
	    delay();
 	}
     else if (c =='y')        /* open/day */ 
        { 
	    red = 1;
	    green = 1;
	    delay();

	}
     else if(c == 'z')        /* open/night */
	{
	    green = 0;
	    red = 1;
	    delay();
	    red = 0;
	    delay();
	}
   }
}