checking sequence using If statement

[beckhamho]

Hi

I am trying to check the sequence using if statement.
first : IR1 and IR3 goes low and IR2 and IR4 stay high
check by while loop, if it is true then go to next if statement.
second : IR1 ,IR2,IR3 and IR4 all goes low.
check by while loop, if it is true then go to next if statement.
lastly :IR1 and IR3 goes high and IR2 and IR4 stay low.

if fulfill above requirement, LCD will increment by one.
I had wrote the program but the program doesn't work.
can someone figure out the problem for me.
below is my code

#include <16f877a.h>
#use delay(clock=20000000)
#fuses hs,noprotect,nowdt,nolvp
#define use_portb_lcd TRUE 
#include <lcd.c>

#define IR1 Pin_A0
#define IR2 Pin_A1
#define IR3 Pin_A3
#define IR4 Pin_A4


void main()
{  
   int people_in = 0, people_out = 0;
   
   set_tris_a(0b00001111);
   lcd_init();

   lcd_putc("\fAutomatic Room");
   lcd_putc("\nLight Controller");
   delay_ms(5000);
   lcd_putc("\f");


display_1st :
   
   lcd_gotoxy(1,1);
   lcd_putc("People in  =  \n");
   lcd_putc("People out =  \n");
   
   lcd_gotoxy(14,1);
   printf(lcd_putc,"%3u",people_in);
       
 do{
   
if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==1 && input(IR4)==1)  
{
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4)));         // (0 AND 0) = 0  (1 AND 1) = 1      0 XOR 1 = 1= TRUE
if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==0 && input(IR4)==0)
{
while((!input(IR1) && !input(IR3)) && (!input(IR2) && !input(IR4)));    // 1 AND 1 AND 1 AND 1 = 1 = TRUE
if (input(IR1)==1 && input(IR3) ==1 && input(IR2)==0 && input(IR4)==0)
            {
               people_in += 1;
               lcd_gotoxy(14,1);
               printf(lcd_putc,"%3u",people_in);
            }
             while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4)));
         }
}
   }while(1); 
}

 

[andre_luis]

Coud you post a flowchart ?

+++

 

[beckhamho]

Hi andre_teprom,

ok,basically my stuff works like this:
IR1,IR2,IR3 and IR4 is always in high stage(1).
I wan to write a program when:
IR1 and IR3 goes low(0) , IR2 and IR4 stay high(1)
then check by while loop,if TRUE then goes to next if statement
IR1, IR2, IR3 and IR4 = 0
check by while loop again, if true then goes to next if statement
IR1 and IR3 goes high, IR2 and IR4 stay low.
if the sequence is correct, then only +1.

 

[alexan_e]

Instead of using all that
if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==1 && input(IR4)==1)
you can use (I assume PINA is the read input reg, but may be different in pic )
if (PINA & 0b00011011)=0b00010010...

and then
instead of
if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==0 && input(IR4)==0)
use
if (PINA & 0b00011011)=0b00000000...

Alex

 

[beckhamho]

Hi alexan_e,
Thanks for the reply.
how about the while loop?
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4)));
should be no problem?

 

[vinodstanur]

i think ur do while logic is correct.
Now u just test LCD section is working properly.
For that just delete the below code in ur program just after the do{;

if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==1 && input(IR4)==1)
{
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4))); // (0 AND 0) = 0 (1 AND 1) = 1 0 XOR 1 = 1= TRUE
if (input(IR1)==0 && input(IR3) ==0 && input(IR2)==0 && input(IR4)==0)
{
while((!input(IR1) && !input(IR3)) && (!input(IR2) && !input(IR4))); // 1 AND 1 AND 1 AND 1 = 1 = TRUE
if (input(IR1)==1 && input(IR3) ==1 && input(IR2)==0 && input(IR4)==0)


Then introduce a delay of about 1s instead of the above code. Then check LCD.

If its working then debug the LOGIC section . Otherwise debug the LCD section.

Actually u should confirm that input(IR1) represent 1st PIN of PORTA .
in hightech c compiler , it is RA0, RA1, RA2, RA3 etc which represent porta bits.
But i think this may be different for different compilers..

In ur compiler if "Pin_A0" represent first bit of PORT A , then u defined
#define IR1 Pin_A0
#define IR2 Pin_A1
#define IR3 Pin_A3
#define IR4 Pin_A4

Now in ur program instead of using IR1, IR2 etc u had used input(IR1),input(IR2) etc.
I am not sure, but just check it.

 

[alexan_e]

Hi alexan_e,
Thanks for the reply.
how about the while loop?
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4)));
should be no problem?

You can simplify that too

but what is the value you want, the following is true in two cases
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4))); // (0 AND 0) = 0 (1 AND 1) = 1 0 XOR 1 = 1= TRUE
while((input(IR1) && input(IR3)) ^ (input(IR2) && input(IR4))); // (1 AND 1) = 1 (0 AND 0) = 0 1 XOR 0 = 1= TRUE

Alex