phase firing angle for fan using at89s52

#include<reg52.h>

#define bargraph P2

sbit  led1 = P3^7;
sbit  led2 = P3^6;
sbit   s1  = P1^0;
sbit   s2  = P1^1;
sbit   s3  = P1^2;
sbit pulse = P0^0;
 
/*code unsigned char timer_l[10]={0x38,0x3c,0x69,0x81,0x99,0xb1,0xc9,0xe1,0x94,0x11};
code unsigned char timer_h[10]={0xfc,0xf6,0xf4,0xf0,0xec,0xe8,0xe4,0xe0,0xdf,0xd9};*/

code unsigned char timer_l[10]={0x38,0x3c,0x69,0x81,0x78,0xb1,0xc9,0xe1,0x94,0x11};
code unsigned char timer_h[10]={0xfc,0xf6,0xf4,0xf0,0xec,0xe8,0xe4,0xe0,0xdf,0xd9};

code unsigned char fonts[10]={0xff,0xfe,0xfc,0xf8,0xf0,0xe0,0xc0,0x80,0x00,0x00};
unsigned char speed;
 
bit on=0;

void delay_ms (unsigned int);


void decangle(void)                              //decrease delay by 1ms
{
if(speed>0)                                      
{ 
speed--;                                        // decrease delay
if(speed!=8)
bargraph=fonts[speed];
}                                                                       
}

void incangle(void)                             // increase delay by 1 ms
{
if(speed<9)
{
speed++;
bargraph=fonts[speed];
}
}

void tx (unsigned char x)
{
SBUF=x;
while(TI==0);
TI=0;
}
 
void int0(void) interrupt 0                     // external interrupt 0 subroutine
{
led1=~led1;                                         // led is on

if(on==1)
{
if(speed==0)
{
pulse=1;                                       // oFF the triace permenately
return; 
}

else if(speed==9)
{
pulse=0;                                       // on the triace permenately
return;                                  
}

else
{
pulse=1;
TL0 = timer_l[9-speed];                               
TH0 = timer_h[9-speed];
TR0 = 1;   
}
}
else
pulse=1;
}


void timer0 (void) interrupt 1
{
TR0=0;
pulse=0;
}

void int1(void) interrupt 2      // external interrupt 1 subroutine
{

if(s1==0)                        // for first key
on=~on;                          // increase counter
       
else if(s2==0)                  // for second key                           
incangle();                     // increase phase angle decrease power
       
else if(s3==0)                 // for third key
decangle();                    // decrease phase angle increase power

delay_ms(300);
} 

void uart(void)
{
SCON = 0x50;   
TH1	 = 0xF3;      
TL1	 = 0xF3;    
TR1  = 1;       
}

void init(void)
{
TMOD=0x21;                                   // initialize timer0 as 16 bit timer , timer1 as 16 bit counter
IT0=IT1=1;                                   // making edge trigger
bargraph=0xFF;                               // making all leds off                  
EX0=EX1=ET0=1; 								 // enable interupts of timer0 abd external interrupt 0 & 1
EA=1;
}

void delay_ms (unsigned int count)
{
unsigned int i;                         
    while(count) {
        i = 115;
                while(i>0) i--;
        count--;
}
}

void send(unsigned char *str) // sending a whole string to port
{
while(*str)
{
tx(*str++);
delay_ms(2);
}
}

void main(void)
{
unsigned char a;
init();
uart();
while(1)                                     // continuous loop 
{

if(on==0)
led2=1;
else
led2=0;

if(RI==1)
{
a=SBUF;
RI=0;
switch(a)
{
case 'A':
speed=0;
send("Motor is off\r\n");
bargraph=fonts[speed];
break;

case 'B':
speed=1;
send("Level 1\r\n");
bargraph=fonts[speed];
break;

case 'C':
speed=2;
send("Level 2\r\n");
bargraph=fonts[speed];
break;

case 'D':
speed=3;
send("Level 3\r\n");
bargraph=fonts[speed];
break;

case 'E':
speed=4;
send("Level 4\r\n");
bargraph=fonts[speed];
break;

case 'F':
speed=5;
send("Level 5\r\n");
bargraph=fonts[speed];
break;

case 'G':
speed=6;
send("Level 6\r\n");
bargraph=fonts[speed];
break;

case 'H':
speed=7;
send("Level 7\r\n");
bargraph=fonts[speed];
break;

case 'I':
speed=8;
send("Level 8\r\n");
bargraph=fonts[speed];
break;

case 'J':
speed=9;
send("Full \r\n");
bargraph=fonts[speed];
break;

default:
on=~on;
if(on==0)
send("Power is disabled\r\n");
else
send("Power is enabled\r\n");
break;
}
}
}                   
}