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In this lecture, I'll show you how to control these simple five volt DC motor using the the RV eight

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eight seven one to break out.

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The particular one that I'm using here is from the fruit.

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It's actually a really good and small package, actually, to control motors like this one.

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Before we get started with the actual demonstration, I just wanted to talk a little bit about this

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module.

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Now, the first thing to notice is that in order for the motor to operate, you need to provide at least

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six point five votes of power to this power as crude terminals.

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From here, I have connected mine to my benchtop power supply and I'm connected on in a moment.

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If you provide anything less than six and a half volts, your motor is not going to work at all.

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The other thing to notice that is important is that this device is able to take instructions, basically

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work with logic levels up to five point five volts.

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So it's going to work well, both with your UNO, which operates at five volts logic level and with

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the SB 32, which operates at three point three.

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So really, you can take it from one project to the other and just use it without having to worry about

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the logic level of each device.

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OK, now part of that, I'm going to show you what the wirings and then have a look at the software.

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So first of all, in this row of pins down here at the bottom with conchi and connected to the ground,

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of course, so that there is a common ground between my external benchtop power supply and the ability

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two, then for VM, I haven't connected it.

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That is the the power voltage for the logic circuit.

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But I've opted to just power the V eight eight seven one from the power supply.

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So I'm leaving the room and connected and I've got in one and into in one in to allow you to control

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the direction of the spin of the rotor of the motor and its speed, the way that have configured it

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here, using in one to control the direction and that is connected to Tapio 21 and into I'm using it

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to control the speed of the rotor and that is connected to Tiberio two on my PSP thirty two.

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And finally I've got my motor connected to the motor scooter and if it does really matter which way

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you connect the wires, it's a symmetrical device.

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All right.

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Now let's have a look at the software side.

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There's no particular library that you need to install in order to control this motor or when it really

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is pinned.

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And and I've also imported the sleep module so can add a bit of delay in between speed settings then.

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I am creating that in one and in two objects.

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So in one, again, it's just a simple G.P.A. pin object used to control the direction.

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So I'm simply turning to Peio twenty one on and off and then control it.

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Which way the rotor is going to spin.

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And then I'm using GWM signals on Tapio two to control the speed.

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Now the speed with it's fast or slow depends on the direction of travel of the rotor.

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So I'll explain the frequency here.

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Default is one thousand but of five hundred hertz frequency work with my motor and again you can experimentally

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try different settings to see which ones work best in the case of your motor.

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Then we go into an infinite loop and I've got two things happening here.

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First, I am sending different settings to the motor so that I change its speed.

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And notice, for example, that when I am moving the motor in one particular direction by turning in

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one two on, then M0 is its fastest setting and the other extend the M one thousand and twenty three

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is when the motor is actually stopped.

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But the exact opposite is happening in reverse.

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So when I turn the in one typical of and that causes the rotor to shift its direction to the other direction

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in the opposite direction, then a high number of m the.

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Value for the duty cycle will cause the Rotha to spin fast where it was slow in the previous direction,

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the opposite direction, and then as the values drop towards zero, the speed of the rotor stops as

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well, where zero in the opposite direction is the fastest setting.

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So we just need to keep in mind that the speed and value and speed have to do with the direction of

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travel of the road.

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So these numbers need to be taken into conjunction with the direction of the rotation and no go together.

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All right, let's do a demonstration.

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So I'm going to turn on my power supply.

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I've said the voltage to six and a half volts, which is the minimum that the Davíð eight eight seven

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one will work with.

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I've got a maximum of two ends and will tend the power supply on.

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All right.

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And can you start the script?

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So moving one direction, let's call that forward and then moving the other direction.

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Let's call that reverse.

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And I can control the speed each time from high to low, just passing the appropriate value for that

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direction of travel of the rotor.

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OK, we'll stop that here.

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Just remember that it is possible to use the chill here in order to figure out what the numbers are

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before you commit them into your sketch.

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So I'll just give you a quick demonstration.

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Let's say that we've got these two Io's in one and two to go for the default frequency, which is 1000

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hertz.

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And let's say that in one is on so called the road of travelling in that direction.

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That seems to be clockwise, let's call it clockwise, for I change duty cycle to zero.

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Is its maximum speed and scope for 1023.

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That stops I for a change in one two of.

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I can see that now it's spinning at the maximum speed, but in the opposite direction for them, go

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for two cycles zero.

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In this direction.

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The rotor stops, whereas in the previous direction, he was at maximum speed, so that's how you can

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just empirically and easily figure out which speed he is setting and direction works best for the situation.