>> I have used the variable "state_var" in many of the functions as well as the main program
an alternative is that i could use "program_state" as it represents various states of the program at different stages and not just the inputs(i have used it for input also)

>> I have written this for loop to break or skip the next display as shown

    for(i=0; i<1; i++) 
{
    lcd_disp1(lcd_door,0);     //prompt the user to press a button to open or close a door
    temp=input_keypad();       //wait and see if the user gives input
    if(temp != ERROR_VAL)break;// if input is given skip the next 2 display statements
                               // and go to the if statement present after this for loop

    lcd_disp1(lcd_change,0);   //prompt the user to press a button to change password
    temp=input_keypad();       //wait and see if the user gives input
    if(temp != ERROR_VAL)break;// if input is given skip the next display statements
                               // and go to the if statement present after this for loop

    lcd_disp1(lcd_exit,0);
    temp=input_keypad();
    //if(temp != ERROR_VAL)break; as you pointed out this is my mistake
}

if(temp==KEY_DOOR_OPENCLOSE)
{
   if(door_state==1)
 {........

 

>>

lcd_disp( QUESTION_MARK_CHARACTER );

 

this is not an input prompt its more like the ****** that appears when we type password in computers


>>(global declaration)

unsigned char  present_key[]="12345600"
 

in the change_key() function
i have used the following code

for(i=0; i<8; i++)
{
   present_key[i] = password[i];
}
 

will the variable, present_key hold "12345600" or the new value assigned to it after reset(i want it to hold the new value not "12345600")