Published April 25, 2018 © GPL3+

Timer with Flashing Lights and Annoying Sound

This is a timer that counts down the time, then sounds an alarm and flashes lights when time runs out.

IntermediateShowcase (no instructions)5 hours2,696

Timer with Flashing Lights and Annoying Sound

Things used in this project

Hardware components

Arduino UNO

Breadboard (generic)

LED (generic)

one green, one yellow, one red

Adafruit Standard LCD - 16x2 White on Blue

Resistor 10k ohm

Resistor 221 ohm

Rotary potentiometer (generic)

ControlEverything.com Piezo Sensor

SparkFun Pushbutton switch 12mm

Jumper wires (generic)

Software apps and online services

Arduino IDE

Story

Introduction:

Timers are useful in many scenarios. Whether you need to make sure that your cookies in the oven do not burn, that your child does not spend more time watching TV than allotted, or that you can beat your friends in a burrito-eating competition and stuff as many burritos into your system within the time limit as possible (I don't know why you would do that, but you do you), timers are important in ensuring that you keep track of time in an effective way.

This is why we were inspired (and low-key forced) to create this wonderful project. This project allows for you to have a beautiful, functional, efficient timer, embellished with LEDs and an annoying alarm-sound-making-thing (see also: piezo) for when the timer runs out.

Wiring:

First, take a look at all of the necessary components. Make sure that you are able to attain each of these, for they are all crucial to the functionality of this timer.

Next, take a look at the Fritzing diagram we have included. It gives you a nice, easy-to-understand view of the wiring and placement of components. Follow that diagram perfectly, and you should be fine. If you still encounter any problems or are confused by the jumble of wires and are not sure where a wire would go based on the diagram, refer to the pictures below. If you are still having trouble, we encourage you to try your best and use your knowledge and intuition to figure it out!

1 / 3 • where wires go on arduino board

The end product should look like this:

final overall wiring

Coding:

Then, take a look at the code we included. It is relatively simple and short, though it may seem somewhat complicated. Copy it down word for word and read the comments, and you should be good. If not, here's a valuable tip: Don't forget those semicolons! ;)

Additional Notes:

Note: We did not further decorate or design our timer for lack of time. However, if you wish to create something that would make the timer appear more like an actual timer instead of just an LCD screen, random components, and a bunch of wires everywhere on a breadboard, go for it! Let your imagination run wild!!! XD

Note: We hope that this timer is useful and worth the time it takes to construct. If, for some reason, you are utterly displeased about something in this tutorial, or have a question, please feel free to leave a comment below! Not that we'll necessarily look at it or anything (we are American high-schoolers who did this for a good grade; be realistic) but you are still entirely free to leave comments. I suppose, then, that if you found anything absolutely superb about our project, also feel free to leave a comment and do a bit of free marketing for us!

Note: We thank you for reading through this huge story and hope you have a fantabulous day till the end of time!

Code

Timer Code

#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

const int switchPin = 6;
int switchState1 = 0;
int switchState2 = 0;
int prevSwitchState1 = 0;
int prevSwitchState2 = 0;
int note = 100;
int seconds = 15; // can change value here to determine how long you want timer to run


void setup() {
  // put your setup code here, to run once:
  lcd.begin(16, 2);
  pinMode(switchPin, INPUT);
  lcd.print(seconds);
  lcd.setCursor(4,0);
  lcd.print("seconds"); // these set up the LCD screen
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT); // these set up the LEDs
}

void loop() {
  // put your main code here, to run repeatedly:
  switchState1 = digitalRead(6);
  switchState2 = digitalRead(13);
  if (switchState1 == LOW) { // if button is not pressed, nothing happens
    digitalWrite(7, LOW);
    digitalWrite(8, LOW);
    digitalWrite(9, LOW);
  }
  while (switchState1 == HIGH && seconds > 0) { //if the button is pressed
    delay(1000);
    lcd.clear();
    lcd.print(seconds - 1);
    seconds = seconds - 1; // timer counts down by 1 second
    if (seconds > 10) {
      digitalWrite(7, HIGH); // green LED is on
      digitalWrite(8, LOW); // yellow LED is off
      digitalWrite(9, LOW); // red LED is off
    }
    if (seconds < 10 && seconds > 5) {
      digitalWrite(7, LOW); // green LED is off
      digitalWrite(8, HIGH); // yellow LED is on
      digitalWrite(9, LOW); // red LED is off
    }
    if (seconds < 5 && seconds > 0) {
      digitalWrite(7, LOW); // green LED is off
      digitalWrite(8, LOW); // yellow LED is off
      digitalWrite(9, HIGH); // red LED is on
    }
    if (seconds <= 0) {
      lcd.clear();
      lcd.print("TIME'S UP!"); // time is up
    }
    while (seconds <=0) {
        tone(10, note);
        delay(300);
        noTone(10);
        delay(300); // makes annoying alarm sound
        digitalWrite(7, HIGH);
        delay(100);
        digitalWrite(7, LOW);
        delay(100); // makes green LED flash
        digitalWrite(8, HIGH);
        delay(100);
        digitalWrite(8, LOW);
        delay(100); // makes yellow LED flash
        digitalWrite(9, HIGH);
        delay(100);
        digitalWrite(9, LOW);
        delay(100); // makes red LED flash
    }
  }
}

Credits

Srija Ponna -20

1 project • 1 follower

Timer with Flashing Lights and Annoying Sound

Things used in this project

Hardware components

Software apps and online services

Story

Introduction:

Wiring:

Coding:

Additional Notes:

Schematics

Timer Fritzing Diagram

Code

Timer Code

Credits

Srija Ponna -20

Comments

Embed the widget on your own site

Timer with Flashing Lights and Annoying Sound

Timer with Flashing Lights and Annoying Sound

Things used in this project

Hardware components

Software apps and online services

Story

Introduction:

Wiring:

Coding:

Additional Notes:

Schematics

Timer Fritzing Diagram

Code

Timer Code

Credits

Srija Ponna -20

Comments

Related channels and tags