CODE

Forum 2005-2010 (read only) General Frequently-Asked Questions
1

Can some one help me with this code and tell me whats wrong

int red = 10;
int green = 11;
int button = 5;

int buttonstate = 0;

void setup () {
  pinMode(red, OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(button, INPUT);
}
void loop() {
  buttonstate = digitalRead(button);
  if (buttonstate == HIGH);
  
  digitalWrite(red, HIGH);
  delay(100);
  digitalWrite(red, LOW);
  digitalWrite(green, HIGH);
  delay(100);
  digitalWrite(green, LOW);
  }
  else {
  
    digitalWrite(red, HIGH);
  digitalWrite(green, HIGH);
}
}
2

You have a semicolon instead of an opening bracket after the if.

Try  if (buttonstate == HIGH)[glow]  {[/glow]
[edit]Debouncing the button is probably not required in this sketch because of the speed of the loop, but if you are going to do something more than experiment with turning LEDs on and off, you should study that topic.
[/edit]

3

Thanks Thats great!!

4

Does anybody no how to do the bit of code where a loop starts depending on how many times you push the button?? :-/

5

Not sure what you mean

6

PSEUDOCODE

int buttonCounter = 0;
loop
  if button is pressed ? buttonCounter++;
  if buttonCounter >= 10 ? doAction();
end loop
7

Thanks Still Not To Sure.

8

Can you give us a better idea of what you're looking for?

Do you want it to perform some action after the button is pressed a certain number of times, or loop once for each button press (i.e. 10 presses means 10 iterations of the loop), etc.?

9

I mean if u press it once then it will do 1 loop but if you press it twice it does another operation! :-/

10

How does it know when you've stopped pressing the button?
Timeout?

11

Do you mean something like this

http://www.ladyada.net/learn/arduino/lesson5.html

/*
 *  Bike light, final version
 */

int switchPin = 2;              // switch is connected to pin 2
int led1Pin = 12;
int led2Pin = 11;
int led3Pin = 10;
int led4Pin = 9;
int led5Pin = 8;

int val;                        // variable for reading the pin status
int val2;                       // variable for reading the delayed status
int buttonState;                // variable to hold the button state

int lightMode = 0;              // What mode is the light in?

void setup() {
  pinMode(switchPin, INPUT);    // Set the switch pin as input

  pinMode(led1Pin, OUTPUT);
  pinMode(led2Pin, OUTPUT);
  pinMode(led3Pin, OUTPUT);
  pinMode(led4Pin, OUTPUT);
  pinMode(led5Pin, OUTPUT);
  
  Serial.begin(9600);           // Set up serial communication at 9600bps
  buttonState = digitalRead(switchPin);   // read the initial state
}

void loop(){
  val = digitalRead(switchPin);      // read input value and store it in val
  delay(10);                         // 10 milliseconds is a good amount of time
  val2 = digitalRead(switchPin);     // read the input again to check for bounces
  if (val == val2) {                 // make sure we got 2 consistant readings!
    if (val != buttonState) {          // the button state has changed!
      if (val == LOW) {                // check if the button is pressed
        if (lightMode == 0) {          // if its off
          lightMode = 1;               // turn lights on!
        } else {
          if (lightMode == 1) {        // if its all-on
            lightMode = 2;             // make it blink!
          } else {
            if (lightMode == 2) {      // if its blinking
              lightMode = 3;           // make it wave!
            } else {
                    if (lightMode == 3) { //  if its waving, 
                lightMode = 0;           // turn light off!
              }
                  }
          }
        }
      }
    }
    buttonState = val;                 // save the new state in our variable
  }

  // Now do whatever the lightMode indicates
  if (lightMode == 0) { // all-off
    digitalWrite(led1Pin, LOW);
    digitalWrite(led2Pin, LOW);
    digitalWrite(led3Pin, LOW);
    digitalWrite(led4Pin, LOW);
    digitalWrite(led5Pin, LOW);
  }

  if (lightMode == 1) { // all-on
    digitalWrite(led1Pin, HIGH);
    digitalWrite(led2Pin, HIGH);
    digitalWrite(led3Pin, HIGH);
    digitalWrite(led4Pin, HIGH);
    digitalWrite(led5Pin, HIGH);
  }

  if (lightMode == 2) { // blinking
    digitalWrite(led1Pin, HIGH);
    digitalWrite(led2Pin, HIGH);
    digitalWrite(led3Pin, HIGH);
    digitalWrite(led4Pin, HIGH);
    digitalWrite(led5Pin, HIGH);
    delay(100);
    digitalWrite(led1Pin, LOW);
    digitalWrite(led2Pin, LOW);
    digitalWrite(led3Pin, LOW);
    digitalWrite(led4Pin, LOW);
    digitalWrite(led5Pin, LOW);
    delay(100);
  }
  if (lightMode == 3)  { // "wave"
    digitalWrite(led5Pin, LOW);
    digitalWrite(led1Pin, HIGH);
    delay(50);
    digitalWrite(led1Pin, LOW);
    digitalWrite(led2Pin, HIGH);
    delay(50);
    digitalWrite(led2Pin, LOW);
    digitalWrite(led3Pin, HIGH);
    delay(50);
    digitalWrite(led3Pin, LOW);
    digitalWrite(led4Pin, HIGH);
    delay(50);
    digitalWrite(led4Pin, LOW);
    digitalWrite(led5Pin, HIGH);
    delay(50);
    digitalWrite(led5Pin, LOW);
  }    
}
12

ye thats more like it thanks :stuck_out_tongue: