طراحی keypad فقط با یک پایه میکرو

سلام .میشه کمکم کنی بگی مشکل این برنامه چیه که خود به خود عدد میزنه؟
#include
#include
#include
#include
#include
#asm
.equ __lcd_port=0x18
#endasm
//#############################################
int key(void);
float _Main(void);
void Mohandes(void);
void Mohasebe(void);
void Alamat(int,int);
float Emoji(int);
//#############################################
float a = 0 , b = 0 , c = 0 , q , t;
int i ;
char y=0 , lcd[25] , z ;
//#############################################
void main(void){
lcd_init(16);
lcd_clear();
lcd_gotoxy(2,0);
lcd_putsf(“JABER NOBAKHT”);
lcd_gotoxy(3,1);
lcd_putsf(“UNI *PAYAM*”);
delay_ms(1000);
lcd_clear();
lcd_gotoxy(1,0);
lcd_putsf(“SH DANESHJUYI”);
lcd_gotoxy(3,1);
lcd_putsf(“9254011017″);
delay_ms(1000);
lcd_clear();
lcd_gotoxy(1,0);
lcd_putsf(“OSTADE RAHNAMA”);
lcd_gotoxy(1,1);
lcd_putsf(“OSTAD HASHEMI”);
delay_ms(1000);
lcd_clear();
DDRB=0x0F;
DDRA=0x07;
DDRD=0x0F;
lcd_init(16);
while (1){
_Main();
}
}
//#############################################################
float _Main(void){
int Loop = 1 ;
y = key();
if( y == 15 ){a = 0 ;b = 0 ;c = 0 ;lcd_clear();return 0 ;}
if( y 9 && y < 16 ){
if( y == 15 ){a = 0 ;b = 0 ;c = 0 ;lcd_clear();return 0 ;}
z = y ;
Alamat(y,1);
while(Loop){
y = key();
if( y == 15 ){a = 0 ;b = 0 ;c = 0 ;lcd_clear();return 0 ;}
if( y 15 ){
lcd_clear();
a= 0 ; b = 0 ; c = 0;
Alamat(y , 2);
z = y ;
Loop = 1 ;
while(Loop){
y = key();
if( y == 15 ){a = 0 ;b = 0 ;c = 0 ;lcd_clear();return 0 ;}
if(y < 10){
a = (a*10) + y ;
itoa(y , lcd);
lcd_puts(lcd);
delay_ms(50);
}else if ( y == 14){
lcd_putchar('=');
Mohandes();
}
Loop = 1 ;
}
}
return 0;
}
//##########################################################
void Mohasebe(void){
if(z == 10)c = a / b ;
if(z == 11)c = a * b ;
if(z == 12)c = a – b ;
if(z == 13)c = a + b ;
ftoa(c , 3 , lcd);
lcd_puts(lcd);
delay_ms(100);
}
//#########################################################
float Emoji(int rr){
q=1;
for(i=0;i<rr;i++)q = q * 2.71728 ;
return q;
}
//#########################################################
void Mohandes(void){
t = (3.1415926535897932384626433832795/180)*a ;
if(z == 16)c = sin(t) ;
if(z == 17)c = cos(t) ;
if(z == 18)c = tan(t) ;
if(z == 19)c = 1/tan(t) ;
if(z == 20)c = sinh(t) ;
if(z == 21)c = cosh(t) ;
if(z == 22)c = log(a) ;
if(z == 23)c = sqrt(a) ;
if(z == 24)c = Emoji(a) ;
ftoa(c , 3 , lcd);
lcd_puts(lcd);
delay_ms(100);
}
//#########################################################
void Alamat(int Moji,int Halat){
if(Halat == 1){
if(Moji == 10)lcd_putchar('/') ;
if(Moji == 11)lcd_putchar('*') ;
if(Moji == 12)lcd_putchar('-') ;
if(Moji == 13)lcd_putchar('+') ;
delay_ms(100);
}
if(Halat == 2){
if(Moji == 16)lcd_putsf("Sin ") ;
if(Moji == 17)lcd_putsf("Cos ") ;
if(Moji == 18)lcd_putsf("Tan ") ;
if(Moji == 19)lcd_putsf("Cot ") ;
if(Moji == 20)lcd_putsf("sinh") ;
if(Moji == 21)lcd_putsf("cosh") ;
if(Moji == 22)lcd_putsf("log ") ;
if(Moji == 23)lcd_putsf("Sqrt ") ;
if(Moji == 24)lcd_putsf("exp ") ;
delay_ms(100);
}
}
//#########################################################
int key(void){
char KEY = 1 ;
while(KEY){
PORTD.0 = 1 ;
PORTD.1 = 0 ;
PORTD.2 = 0 ;
PORTD.3 = 0 ;
if(PIND.4 == 1){return 7 ; KEY = 0;delay_ms(50);}
if(PIND.5 == 1){return 8 ; KEY = 0;delay_ms(50);}
if(PIND.6 == 1){return 9 ; KEY = 0;delay_ms(50);}
if(PIND.7 == 1){return 10; KEY = 0;delay_ms(50);}
//==========================================
PORTD.0 = 0 ;
PORTD.1 = 1 ;
PORTD.2 = 0 ;
PORTD.3 = 0 ;
if(PIND.4 == 1){return 4 ; KEY = 0;}
if(PIND.5 == 1){return 5 ; KEY = 0;}
if(PIND.6 == 1){return 6 ; KEY = 0;}
if(PIND.7 == 1){return 11; KEY = 0;}
//==========================================
PORTD.0 = 0 ;
PORTD.1 = 0 ;
PORTD.2 = 1 ;
PORTD.3 = 0 ;
if(PIND.4 == 1){return 1 ; KEY = 0;}
if(PIND.5 == 1){return 2 ; KEY = 0;}
if(PIND.6 == 1){return 3 ; KEY = 0;}
if(PIND.7 == 1){return 12; KEY = 0;}
//==========================================
PORTD.0 = 0 ;
PORTD.1 = 0 ;
PORTD.2 = 0 ;
PORTD.3 = 1 ;
if(PIND.4 == 1){return 15; KEY = 0;}
if(PIND.5 == 1){return 0 ; KEY = 0;}
if(PIND.6 == 1){return 14; KEY = 0;}
if(PIND.7 == 1){return 13; KEY = 0;}
//=============================================================================
PORTC.0 = 1 ;
PORTC.1 = 0 ;
PORTC.2 = 0 ;
if(PINC.5 == 1){return 16 ; KEY=0;}
if(PINC.6 == 1){return 17; KEY=0;}
if(PINC.7 == 1){return 18 ; KEY=0;}
//=====================================================
PORTC.0 = 0 ;
PORTC.1 = 1 ;
PORTC.2 = 0 ;
if(PINC.5 == 1){return 19 ; KEY=0;}
if(PINC.6 == 1){return 20 ; KEY=0;}
if(PINC.7 == 1){return 21 ; KEY=0;}
//=====================================================
PORTC.0 = 0 ;
PORTC.1 = 0 ;
PORTC.2 = 1 ;
if(PINC.5 == 1){return 22 ; KEY=0;}
if(PINC.6 == 1){return 23 ; KEY=0;}
if(PINC.7 == 1){return 24 ; KEY=0;}
KEY = 1 ;
}
}
//############################################################

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