The analog output and input of Arduino

Alright, let’s break down what you need to know about the analog input on the Arduino board! So, you’ve got your Arduino that has digital pins up top and analog input pins at the bottom—those are labeled A0 through A5.
Good news: you don’t have to mess with setting pin modes for analog inputs, unlike what you’d do with digital pins.
Now, when you read the A0 pin, you’re going to get values ranging from 0 to 1023, which comes from its 10-bit reading capability.
Some other Arduino models crank it up to 12 bits, letting you read up to 4095! And hey, just a little tip: make sure to use pull-up or pull-down resistors to keep those input pins from floating around, which can cause you to get some random and tricky values..

So, let’s dive into floating states on Arduino and how they help us get random values! Basically, when you’re initializing the random seed for generating those elusive random numbers, the floating state comes into play.
It’s pretty neat because when you read analog values in this state, it adds a bit of randomness—think of it like a surprise party where the input can fluctuate wildly between 0 and 1023.
But keep in mind, if you’re using actual sensors or pots, you’ll want to have a pull-down or pull-up resistor in place.
Plus, some digital pins on your Arduino can output PWM for analog outputs, with pins 3, 5, 6, 9, 10, and 11 in the mix, and guess what? Pin 9 is the selected star of the show for this setup!.

Let’s dive into Pulse Width Modulation, or PWM for short, and how it affects brightness levels! We kick things off by setting the PBM to 9 and the pin mode to PWM output, ensuring the output starts off as ‘off’—this really helps us keep track of what’s going on.
Now, picture this: we’ve got an LED connected to a potentiometer.
When you twist that potentiometer to small values, the LED’s brightness is pretty dim, but crank it up, and it’s shining bright, thanks to the handy map function we’re using.
With the ADC value coming from our analog input—which ranges from 0 to 1023—we’re storing this in ‘value’; but here’s the kicker: 8 bits just can’t handle that range, so we’re rolling with 16 bits instead.
Finally, to adjust the voltage in a smooth way, we convert that ADC value from its hefty range down to 0 to 255, because our analog write function loves to work in the 8-bit space.
Pretty neat, right?.

So, let’s break it down! First off, when you convert a value and assign it to brightness, that’s what controls the voltage on a specific pin through analog write.
Pretty neat, right? By throwing in a little delay of 100, you can manage the output just like you can fiddle with the resolution during an analog read.
And here’s a cool tip: some boards even let you bump the resolution of your analog PWM up from the standard 8-bit to 10-bit or 12-bit.
Once you’ve made those adjustments, you can set your analog write to any level you want, giving you full control over both inputs and outputs.
In our last session, we dove into the analog side of things with Arduino, and guess what? Next up, we’ll be jumping into serial communication between the Arduino and your PC!.