Arduino Lesson 3

Adding a button! I carried many of the skills I learned last week over to this week.

🎉 #arduino #exercises

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Now, the button controls the fade!

⬆️ #arduino #exercises

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Thank you to my classmates Hannah and Antya, for assisting me with this exercise! Here’s the code we came up with…

Fade with Button

int led = 9; // the PWM pin the LED is attached to
int brightness = 0; // how bright the LED is
int fadeAmount = 1; // how many points to fade the LED by
const int buttonPin = 2; // the number of the pushbutton pin
const int ledPin = 9; // the number of the LED pin

// variables will change:
int buttonState = 0; // variable for reading the pushbutton status

// the setup routine runs once when you press reset:
void setup() {
// declare pin 9 to be an output:
pinMode(led, OUTPUT);
// initialize the LED pin as an output:
pinMode(ledPin, OUTPUT);
// initialize the pushbutton pin as an input:
pinMode(buttonPin, INPUT);

void loop() {

// read the state of the pushbutton value:
buttonState = digitalRead(buttonPin);

// check if the pushbutton is pressed.
// if it is, the buttonState is HIGH:
if (buttonState == HIGH) {
//if the button is pressed,increased fade amount by 1
fadeAmount = fadeAmount + 5;

// set the brightness of pin 9:
analogWrite(led, brightness);

// change the brightness for next time through the loop:
brightness = brightness + fadeAmount;

// reverse the direction of the fading at the ends of the fade:
if (brightness <= 0 || brightness >= 255) {
fadeAmount = -fadeAmount;

// wait for 30 milliseconds to see the dimming effect



One thought on “Arduino Lesson 3”

  1. yeah, nice! I can see how this has similar elements to Hannah’s color mixing code, I bet if you go check her blog post out, it would make a lot of sense now that you’ve built this fade controller. Good work!


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