Keypad scaning problem.

[HerohetoChakma]

I have create a program by which i can set two digit desire set point by using 4*3 Membrame keypad that will show in LCD display. But when i simulate my program in protious it is work by trying more times. Sometimes it dosn't work. But every key is ok. I means sometimes they are ok. Sometimes i can set only one digit number. When i simulate my program an error message is show that simulation can't run due to excessive load. My code are given bellow. How can i solve this problem? Could anybody help me please?????????????
// Keypad scanning functions
//=============================================================================
void clearrow1(void) //clear the 1st row and set the others
{
RC7=0;
RC6=1;
RC5=1;
RC4=1;
}
void clearrow2(void) //clear the 2nd row and set the others
{
RC7=1;
RC6=0;
RC5=1;
RC4=1;
}
void clearrow3(void) //clear the 3rd row and set the others
{
RC7=1;
RC6=1;
RC5=0;
RC4=1;
}
void clearrow4(void) //clear the 4th roW and set the others
{
RC7=1;
RC6=1;
RC5=1;
RC4=0;
}
void scancolumn1(void)
{
if(RC0==0) //if key '1' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st word
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of nuum_count //variable
send_char('1'); //Display the symbol '1' at LCD
keyin[num_count]='1'; //Stall the '1' value at the keyin array
num_count+=1; //increase the num_count variable's value by 1 //and the result stall back to the variable
}
else if(RC1==0) //if key '2' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('2'); //Display the symbol '2' at LCD
keyin[num_count]='2'; //Stall the '2' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC2==0) //if key '3' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('3'); //Display the symbol '3' at LCD
keyin[num_count]='3'; //Stall the '3' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
}
void scancolumn2(void)
{
if(RC0==0) //if key '4' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('4'); //Display the symbol '4' at LCD
keyin[num_count]='4'; //Stall the '4' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC1==0) //if key '5' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('5'); //Display the symbol '5' at LCD
keyin[num_count]='5'; //Stall the '5' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC2==0) //if key '6' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('6'); //Display the symbol '6' at LCD
keyin[num_count]='6'; //Stall the '6' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
}
void scancolumn3(void)
{
if(RC0==0) //if key '7' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('7'); //Display the symbol '7' at LCD
keyin[num_count]='7'; //Stall the '7' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC1==0) //if key '8' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('8'); //Display the symbol '8' at LCD
keyin[num_count]='8'; //Stall the '8' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC2==0) //if key '9' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('9'); //Display the symbol '9' at LCD
keyin[num_count]='9'; //Stall the '9' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
}
void scancolumn4(void)
{
if(RC0==0) //if key '*' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('*'); //Display the symbol '*' at LCD
keyin[num_count]='*'; //Stall the '*' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC1==0) //if key '0' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('0'); //Display the symbol '0' at LCD
keyin[num_count]='0'; //Stall the '0' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
else if(RC2==0) //if key '#' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('#'); //Display the symbol '#' at LCD
keyin[num_count]='#'; //Stall the '#' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
}
}