I am wiring some LED's with buttons to trigger them but i don't know if i have the wiring right?

enter image description here


    /* switch
 * Each time the input pin goes from LOW to HIGH (e.g. because of a push-button
 * press), the output pin is toggled from LOW to HIGH or HIGH to LOW.  There's
 * a minimum delay between toggles to debounce the circuit (i.e. to ignore
 * noise).  
 * David A. Mellis
 * 21 November 2006

int inPin = 2;         // the number of the input pin
int outPin = 13;       // the number of the output pin

int state = HIGH;      // the current state of the output pin
int reading;           // the current reading from the input pin
int previous = LOW;    // the previous reading from the input pin

// the follow variables are long's because the time, measured in miliseconds,
// will quickly become a bigger number than can be stored in an int.
long time = 0;         // the last time the output pin was toggled
long debounce = 200;   // the debounce time, increase if the output flickers

void setup()
  pinMode(inPin, INPUT);
  pinMode(outPin, OUTPUT);

void loop()
  reading = digitalRead(inPin);

  // if the input just went from LOW and HIGH and we've waited long enough
  // to ignore any noise on the circuit, toggle the output pin and remember
  // the time
  if (reading == HIGH && previous == LOW && millis() - time > debounce) {
    if (state == HIGH)
      state = LOW;
      state = HIGH;

    time = millis();    

  digitalWrite(outPin, state);

  previous = reading;

note The code is not set to the pins yet.

  • Its not working or what? The schematic looks right. Only you have 2 inputs and 2 outputs. And in code you define wrong pins
    – Martynas
    Commented Oct 22, 2014 at 6:13
  • @Martynas So i have the wiring right?
    – Timothy
    Commented Oct 22, 2014 at 6:22
  • Yes. Only thing. Don't use voltage from batteries 4x1.5=6 for input. Feed arduino from batteries, and use 5V output to feed buttons
    – Martynas
    Commented Oct 22, 2014 at 6:24
  • @So you mean plug the battery to Ground and Vin then run the 5 volt rail to the breadboard?
    – Timothy
    Commented Oct 22, 2014 at 6:25
  • 1
    Let us continue this discussion in chat.
    – Martynas
    Commented Oct 22, 2014 at 6:40

1 Answer 1


The wiring is correct, but inPin in your code is set to 2, which is D4 on the Nano, while you have your signal wires going to D7 and D6 in your schematic.

Similarly, outPin is set to 13 in your code, which is D9 on the Nano, but your schematic shows the LEDs connected to D5 and D4.

I would also put the resistor going from the other pin on the switch to 5V, having the digital input connected directly to GND, but I'm not sure if that will affect power consumption, so it's probably more just a matter of personal preference.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.