second "if" loop doesn't stop looping.

Hi Friends,

Working on my project here, decided to add a button to get into setup, and use the two others to go up and down. It's easier. But now I run these two if loops, the first one works fine, one click gives me one increment, but as soon as I add the down counter, it just keeps on ticking down. No matter if the button is HIGH or LOW, and if I push the + button, the counter goes up one and back down and down.

I checked the wires, buttons work fine, 0v and 5v for both, the button2 is LOW.

Code:

 void loop()
 {
  button5 = digitalRead(buttonPin5);
      if(button5 == HIGH);               //button5 is held high for the time being.

       {
       button4 = digitalRead(buttonPin4);  // start loop
       button2 = digitalRead(buttonPin2);
       
        if(button2 == LOW && button4 == LOW)  //both low, nothing happening
          {
           delay(500); 
          }

        if(button4 == HIGH)                  //button4 HIGH count up
          {
           digitalWrite(13, HIGH); //LED
           yh++;
           delay(200);
           Serial.println(yh, DEC);
           digitalWrite(13, LOW);
           }

        if(button2 == HIGH);       //button2 HIGH count down, here's the problem.
           {
            yh--;
            delay(200);
            digitalWrite(13, HIGH); //LED 
            Serial.println(yh, DEC);
            digitalWrite(13, LOW);
            }
            
      }
 }

None of that is an actual loop. Also, if those aren't meant to be exclusive checks, if both 4 and 5 are high, it will end up making yh the same thing as it was before (button4 will increment it, button2 will decrement it).


Quzah.

Never mind, I found the problem the second if loop has a ";" at the end, and that's what the problem was, now it's working fine.

Sorry for the wasted bandwidth.

Thanks quzah, how would I make them exclusive checks?

You could do:

Code:

if( button one is true && button two is not )
{
}
else
if( button two is true && button one is not )
{
}
else
{
    ...some other combination is in effect...
}

Quzah.

Thank you quzah, I'm slugging through this with great enthusiasm.
My only wish would be to have started ten years ago.
Lucky for me I don't have to use pointers yet, or call on functions outside the loop.
But I feel it won't be long before I do because I already have a timer.h file I can use to delay while I'm doing something else.

But now back to my program, I need to get this thing done before the weekend.
Believe it or not, I spent the whole day trying to get this stupid button to work.

Originally Posted by RobertD

Never mind, I found the problem the second if loop has a ";" at the end, and that's what the problem was, now it's working fine.

That wasn't the only one with a semicolon at the end of the test:

Code:

if(button5 == HIGH);

... and it's not a loop (to reiterate what quzah stated).

And that is precisely why an "if" (or "for" or "while") should be written like this:

Code:

if (condition) {
    statement1;
} else {
    statement2;
}

Instead of like this:

Code:

if (condition)
{
    statement1;
}
else
{
    statement2;
}

MUCH less likely to make that kind of mistake.

I hate that style of indenting. An opening brace should be on the same level of indentation as a closing brace in my opinion. But that is really a different thread entirely.


Quzah.

Originally Posted by quzah

I hate that style of indenting. An opening brace should be on the same level of indentation as a closing brace in my opinion. But that is really a different thread entirely.


Quzah.

There's always my way ... that nobody likes but me...

Code:

if (x = 11)
  { dothisthing(); }
else
  { dothatthing();
     andalittleofthis(); }

It looks a lot nicer when syntax highlighted and it produces very compact code... but I'm thinking it's as non-standard as it gets.