7_7 Button Raises and Lowers Brightness

Buttons Raise and Lower LED Brightness

Code

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/* Pressing one button raises the brightness of and LED, pressing another button lowers the brightness */ int brightness = 0; //create a variable named 'brightness' that is an integer (whole number) and starting value of 0 void setup(){ pinMode(9,OUTPUT); //LED. analogWrite() function works on pins 3,9,10,11 and lets you send values from 0 to 255 pinMode(7,INPUT_PULLUP); //button 1 (raises brightness) pinMode(4,INPUT_PULLUP); //button 2 (lowers brightness) } void loop(){ analogWrite(9,brightness); //use the brightness variable to determine how bright the LED is (0-255) if(digitalRead(7)==LOW){ //If the button 7 is pressed brightness++; //increase brightness variable by 1 delay(20); //a delay means you can see the fade. Without it, the light value jumps too quickly } if(digitalRead(4)==LOW){ //If button 4 is pressed brightness--; //lower the brightness on the LED delay(20); //delay allows you to see the fade. // -- is shorthand for 'subtract one from the variable' } } // (c) 2023 Let's Start Coding. License: www.letsstartcoding.com/bsdlicens
 

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