Easy counter

Using Arduino Programming Questions
1

Hi

I think it's very simple problem.

I want a counter that's counts up from 0 to 3 and then Counts down from 3 to 0 then i push the button up or down.

I Think its wrong in the IF(….)

const int buttonPinup = 2; // the number of the pushbutton pin
const int buttonPindown = 3; // the number of the pushbutton pin

// variables will change:
int buttonState1 = 0; // variable for reading the pushbutton status
int buttonState2 = 0;
int count = 0;

void setup() {
Serial.begin(115200);
pinMode(buttonPinup, INPUT);
pinMode(buttonPindown, INPUT);
}

void loop() {

// read the state of the pushbutton value:
buttonState1 = digitalRead(buttonPinup);
buttonState2 = digitalRead(buttonPindown);

// check if the pushbutton is pressed. If it is, the buttonState is HIGH:
if (buttonState1 == HIGH) {
if ( count >= 0 and count == 2 ); {
count = count +1;
delay(500);
Serial.println(count);
}

}
else if (buttonState2 == HIGH) {
if (count >= 0 and count <= 2); {
count = count -1;
delay(500);
Serial.println(count);

} }}

2

There's a semicolon here that should not be:

    if ( count >= 0 and count == 2 ); {

Same thing further down too.

Also, if you're checking for count to be two, why do you need another check that it's greater than or equal to zero?

3

I see i wrote ==2 and <=2 but nothing change.
Then I test it dont stop counting with number 3 or 0.

I change to:

if ( count < 3 ); {
count = count +1;
delay(500);
Serial.println(count);

What should i wrote? It dont stop with number 3!

4

Your if statement is still broken, it has no effect at all because of the semicolon.

5

So easy!!!

Thanks very much!!!

6

Are where any easy way that you must release the button between every up/down counter?

7

plutten:
Are where any easy way that you must release the button between every up/down counter?

See if INPUT_PULLUP makes any difference.

8

Thanks but sorry, it didn´t help.

Another way to do it?

9

You need to increment your count when the button BECOMES pressed, not when it IS pressed.

Look at the StateChangeDetection example in the IDE.