Randomly Blinking LEDs on Arduino UNO

Rajesh Majumdar
Aug 22, 2017 · 1 min read

Hi guys,

So today I got my hands on an Arduino UNO R3, and this was the first time I was working on some hardware stuff, as I am not interested in both hardware and electronics. But I was interested in “Hardware Hacking” so bought one.

First thing I did after getting the Arduino, I googled “Arduino for beginners” but that was confusing. So I watched a youtube video on “Blinking a LED on Arduino”. That was enough to understand basics about Arduino. I did the same and Hooray! I build my first project on Arduino. But I was not happy, so I thought to make something different out of it. So I added some more LEDs and thought to blink them randomly and fast.

Now this was looking awesome, then I thought to make these LEDs respond on music beats, which I am working on for that I need some sensors, so those are on the way. For now let me share that simple C code with you.

int red1 = 13;
int red2 = 12;
int yellow1 = 11;
int yellow2 = 10;
int green1 = 9;
int green2 = 8;
long randOn = 0;
long randOff = 0;
void setup() {randomSeed(analogRead(0));

pinMode(red1, OUTPUT);
pinMode(red2, OUTPUT);

pinMode(yellow1, OUTPUT);
pinMode(yellow2, OUTPUT);
pinMode(green1, OUTPUT);
pinMode(green2, OUTPUT);
}
void loop() {
randOn = random(100,1200);
randOff = random(200,900);
const byte leds[] = {13,12,11,10,9,8};
byte led;
led = leds[random(0,6)];

digitalWrite(led, HIGH);
delay(50);
digitalWrite(led, LOW);
delay(50);
}

Here I attached these 6 LEDs in input 8–13 on Arduino board.

Thanks!

)
Rajesh Majumdar

I turn coffee into 0xc0f3e

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