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For our LED random brightness project we need first to get our Arduino board
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place it somewhere here and then get one led i'm gonna place it here
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and i also need one resistor a 220 ohm resistor i i'm gonna place this in the negative side
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and then connect that one the negative side of the LED to the ground pin of the
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Arduino board and the positive side I'm just gonna connect one jumper wire and
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connect it to digital pin 3 so to arrange my wires here and basically this
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is the breadboard diagram for our project now let's go to the code of our
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random brightness for one LED project okay so for the variables we need a
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variable to hold our random values we need random numbers from 0 to 255 since
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these are the PWM values that we need PWM values these are explained thoroughly in the fade in fade
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out project okay so 0 to 255 that is an integer so we can use int data type and let name our variable
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as random led val we don't have to assign it any value yet since anyway in the loop function later
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on we will assign it random numbers and the second variable that we need will be for our led which is
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connected to digital pin 3 so that's in and let's give it a name let's say led pin with a value of
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3 for digital pin 3 those are all the variables we need for the setup we just need first to set up
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our LED pin as an output pin so that's pin mode LED pin and output
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and then there's another thing we need to do in the void setup
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now every time we or Arduino generates random numbers it gets it from a default
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seed like a basis where to get these random numbers so we need to change that one we need to
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give it a random seed okay and where do we get this it could be uh the time of the day or a week
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day or a value from a pin an arena pin which is not connected to anything so for example an og
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pin which is not connected to anything will give us floating values from 0 to 1023 So let get that seed We type in og read
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So we are reading og 0 and we just have to make sure that og pin 0 is not connected to anything
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That is all for our setup function. Let's now go to the loop
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For the loop function, so the first thing we need to do here is to assign the random number for our random led
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val this variable we now need to assign it a number from 0 to 255 okay so we simply need to
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type in that variable name random led val and then to get a random value we type in the random
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function and then the minimum number that we want and the maximum number that we want
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However, I'm going to type here 256 because based on the syntax, anything we write here
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that number will be subtracted by 1. So basically, we get 0 and 255
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Okay. Next is so now we have our random LED valve which contains a random number we use that number to write to our LED so we type in og write so we just have to make sure that the LED is connected to a PWM pin for this to work So og write and then our LED pin
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where the LED is connected to and the value of its brightness the PWM value and we will get that
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from our random lead val variable okay so that's it we um we give it a delay you can
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type in any number here i would like to give it a delay of 100 milliseconds
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so what happens is after 100 milliseconds it will go back to the first code inside our loop function
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which is random so every 100 milliseconds our random lead valve variable will get a random
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number from 0 to 256 and that number is what arduino will use to write to our lead pin
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so in this way our led will get random brightness every 100 milliseconds so that's it i'll just have
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to upload oh check first i have the correct board and correct port okay and upload save that one
