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But in this lecture, I'm going to show you how to use a mini circumlunar like the one on this video.

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Now, I just wanted to mention before the game is that this particular a motor that I'm using is damaged

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the integrated stops that it contains in this container to prevent the shaft from moving beyond its

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available range, which usually is about zero degrees or most properly built and working in good working

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order.

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Servo motors can operate at about a zero to one hundred and eighty degrees.

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That's the range of movement that they have.

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This particular one is damaged.

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So if I tried to turn the shaft to anything less than 20 degrees, it's going to go beyond its limit

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and actually get it to act as a continuous rotation.

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Seven.

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I'm going to show you what I mean by this at the moment when I do the demonstration.

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But I thought I would still use this just to show you how we can control the range of motion of this

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sort of a motor, even if it is damaged in terms of connections.

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Servo motors come with a with three wires that are color coded.

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So the brown wire goes to ground.

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The orange you should it's an orange or red wire goes to five four votes.

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It's connected to the final pin on the specific two and the orange one here.

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So there's the red one four five volt the orange one in this color coding of connected to Tiberio two.

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Or you can connect it to any capable p. m..

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Higher on your ID to anyone who do this embedded with the hardware.

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Let's have a look at the software side now.

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We've got a demo script here that I found here, and this is the URL where you find the original with

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additional documentation written by George and take from take to think it works really well.

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The principle of operation of this script is to use a mapping function, this function right here.

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So what this function does and actually how it works, it works in a very similar way to how the map

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function works in the doing the language.

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So if you're familiar with it, actually, if you're not familiar with the mapping function and the

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idea is that you have a number X which is within a particular range, and then you want to convert it

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into a new range or a different range, which you can mark in the parameters here and the map function.

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And what you get back is a number that falls in the target range.

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The original, again, falls within this range.

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In this example, the Y would be the equivalent number that falls within a new range.

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And that's exactly how this map function works in this example script.

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So what we going to do with a map function is to give it a number in degrees which falls in the range

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of zero to 180 degrees.

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And what this map function does is to give us back a number which represents a p m value, which falls

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in the range of twenty to one hundred twenty.

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So then that value can be given to the tuti method of the object and that make the shaft work and rotate

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the shift to the appropriate degree value.

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So that's the basis of this script.

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As you can see, it's self-contained.

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We don't need to import anything other than the machine module and the time module for a bit of a delay.

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There is pretty self-explanatory by this time.

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As you've been following through this course, we'll create the several PIN object as connected to the

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orange wire from the server motor to Tapio to it that goes there.

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Then we get the object connected to that several Penge Aperio two.

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We set the frequency for the object and found that 50 Hertz works for this particular server motor.

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This is something that I found empirically.

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You may need to tweak that number a little bit if you're using different many servo motor, but just

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start with 50 hertz and see how you go.

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We reset the server motor by sending value pitiably in value zero to the object via the duty method.

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We've already seen the map and several functions.

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Let's go ahead and use the server functions.

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So here we go.

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This is, for example, will drive the shaft of the mini servo motor to twenty degrees and then wait

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for one second there.

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Then move it to 90 degrees, wait for another second and move it to the other extreme, 170, and wait

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for another second notice here that I'm not going to zero because I found that if I did go to zero,

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then driving the mini survey motor to a degree value that is beyond its capability to handle.

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So that just makes it rotate as if it was a continuous rotation.

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Seven motor up.

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Change this to a zero.

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A bit later to see so we can see what the effect of this is.

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And I'm doing the same thing up here at the other extreme.

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And I'm not going all the way to one hundred and eighty degrees because my mini motor miniature memory

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can't handle it.

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So I'm just going up to one hundred seventy degrees.

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That is his current limit after that, going into an infinite loop where I'm simply moving the mini

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servo from its lowest, it's highest degree and a step of ten can change that to whichever step you

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want and staying there for half a second and then moving back from the highest degree value to the lowest

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degree value that it can handle at a step of minus 10 degrees.

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All right.

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I'm going to upload this sketch, this script.

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To the east because they didn't see it in action.

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Go up and then moving down.

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No problems.

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Now see what happens if I change this to zero and that to zero as well, that control, say, to stop

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execution and then save it.

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And I will run it again.

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Try one time.

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OK, try again.

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You have my minister right now working as if it was a continuous rotation system, so going up there's

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no problem of the 170 is OK going back.

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Once it goes past 20.

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It continues to rotate beyond its limits.

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All right, that's about it.

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So, as you can see, it's fairly easy to control a sort of a motor using the example sketch that I've

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shown.

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You can move on to the next picture now where I'll show you how to control a DC motor using the Garveys

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eight eight seven one.