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But in this lecture, I'll show you how to use pulse width modulation to control the intensity of the

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light that comes out of infinity in this case, just like in the previous examples of conditionality

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connected to Chipo 21.

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Now, talking about the hardware, before we move on to the software side, just wanted to remind you

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that on the E.S.P 32, you're looking here at the PIN layout chart.

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Just zoom out for a second.

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You can see that any Tapio with a tilt next to its pin is capable in this case.

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For this example, I'm using Chip here you are 21, which is capable.

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So as long as there is a tilde next to the pin that you want to use and it is free, it's not occupied

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with something else, then you can apply and function to it.

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All right, let's have a look at the script here, so I have created a little demonstration file called

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Fadeout.

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As you can see, it's on my computer file system.

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I haven't copied it over to the three yet.

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Having a quick look at it, I am going to be using, of course, repeatably m.

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Module to control the ability and of course, the documentation being right here and also using a function

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called range that comes with the Standard Micro Python and Python libraries and its documentation link.

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Is this having a quick look at those two resources?

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You can see that the W.M. functionality is part of the machine module and you can use this notation

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to create a piece, an object.

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You basically just call them.

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Then you pass on the GPO that you want to use.

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You can read or set the frequency of your M channel.

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The default is 1000.

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So if you don't set it and the default of 1000 is going to be used and then you can set its duty cycle

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by calling the duty function and putting the duty cycle just a number between zero and one thousand

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twenty three.

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As you can see here, the documentation, if you don't pass a parameter in the function, then this

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would return the current duty cycle.

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So you can always check to see what it is before you change it.

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It's another example here of how you can create a W object and set both its frequency and its duty cycle

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in one in one function like that.

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So I'm using the M functionality.

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First of all up here, I'm just going with the default C, I'm just setting the pin to be a twenty one

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and then down here in the infinite loop using the wild true loop, I've got a couple of loops.

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The first one is counting up for the two to circle from zero to one thousand twenty three in step five

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and then calling the duty cycle and setting the -- cycle according to what it is inside the loop.

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And then the second that I'm counting down, that's within range function is useful.

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I'm counting down from one thousand twenty three to zero in step, negative five minus five each time

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going for a little sleep and then continuing with the loop.

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So the built in function range looks like this.

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It's got to overloaded functions.

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The first one just has one parameter, the stop.

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So if you go for range and then you give it a number, then it will count from zero up to that number

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in step one.

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The alternative is to go for this function here, which requires three parameters start to stop.

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And then the step, which is the one that I'm using right here.

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That makes it easy to count from a number to any other number using any step that you want.

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All right.

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So I'm going to upload this as a copy to the marketplace and device.

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It's called his fate dot p y.

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All right, and loaded into phony just to get rid of the one stored on the local filesystem, so don't

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confuse it to this.

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And I'm going to press the wrong button to get it to start.

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And then you get the LDH on and off.

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For the speed things up a little.

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Which case I will need to interrupt.

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Before I can make any changes to the sketch and then let's make that say 15 and minus 15 and save and

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play again.

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You can see that it now fades on and off faster, so you can either change the step parameter or reduce

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or increase the sleep amount of time, and that will have an effect on the speed with which the on and

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of.

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All right.

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That was easy enough.

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Let's move on to the next lecture where I show you how to read the state of a button, and we do that

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in a few variations, a few different ways by which you can read the state of the.