 It's me, JP, and it's time for JP's product pick of the week. Right here in my sort of post-apocalyptic workshop, I had to move a ton of stuff from over there. I can see right there. Patching a hole in the back of the garage. This was a garage before I turned it into my workshop, and the previous owner had knocked out what five or six of the studs that hold up the wall to make a hole, to make a box, to fit like his bumper on his car, like a huge Buick or something like that. So it's been like that for 20 years or more now, and I'm finally fixing it. So pardon the mess, the messier, the usual mess here. Let's see. So, oh, also, full disclosure, because we're doing those things with machine learning, or if used to call it artificial intelligence, but with machine learning, a friend of mine made that image using one of the machine learning tools and gave it a description, and then I superimposed part of my face. Most of it, including the beard and the hair, were from the AI and looked weirdly like me, and the workshop looks weirdly like mine. That's from a description. I feel like it's been training on my videos or something, because, hey, weird. And since I'm talking about the process here, half of that background wasn't there, and I added it with Photoshop's generative fill. So the, to the right, screen right, or character right, screen left. None of that was there, and in Photoshop I said extend the background, and it just nailed it, which is wild. So that's that. All right, let's get on with this show. Woo, hey, what's happening? Okay, so first of all, if you wanna go and check out the product pick and get a jumpstart on it, you can head to that URL or to that QR code. It is product ID 3190, so you can jump on over there. You can watch the show from inside there. We broadcast the show inside of the page, and you will see that it is on discount. You can get it for half price during the show. After the show it'll go back to full price, but if you wanna get this week's product pick, throw some in your cart and maybe some other things, and just hit go before the end of the show, and you'll get it for half price. But before I say anymore, let's have Lady Aida jump back a little bit in time to tell you about this week's product. Take it away, Lady Aida. We have a little motor driver. So it's a cute little motor driver, but despite it being cute, it's quite powerful. So some people wanted some high power motor control. These can do up to 3.6 amps up to 45 volts. They're very basic. It just uses two PWM or digital inputs to control the motor, but really good when you have just a large motor. It also has built-in current limiting, which I kinda like, so you can limit the current using an external resistor. It's not a sensor resistor, it's just not in line with your signal, so it doesn't get hot. You don't have to worry about having a 0.001 ohm resistor. Instead, I guess it's used as a current multiplier or internal circuit that is current limiting. So there's an external resistor, about 30K, is what we put on there to start, but you can adjust it as necessary to change the current. So we thought, set the current limit to about two amps. That's a pretty good place for most motors. So when you put it on your rover, if you stall out, you won't tear through your battery, you'll just stop working instead of just fighting. The motor is continuing to fight whatever is obstructing it. And I've got a simple demo here, so this is just the Arduino compatible, and then they have it hooked up to the two PWM outputs, so this is nine and 10. And then I just slowly ramp up and down. It only drives one DC motor, but if you wanna have that much current going through a motor anyways, you'll wanna have a separate chip. So let me turn this on. Give it a second. Just start up. There you go. Okay, I don't know why I was... So it speeds up the motor one direction, slowly speeds up, speeds back down, and then goes the other direction. So it's just a very simple demo of... Sorry, I'm still loud. It's a very simple demo of a motor. And then if you're running the motor and you hold this so it can't turn, it does fight, but it eventually just like, it doesn't keep going after a certain current limit. So it's good for your batteries if you have a power supply that's in the middle. See what I find, I just keep going. Yeah. Does that. It also has internal thermal protection, undervoltage, a couple of other things. That's a cute little motor driver handy for robots and stuff. Okay. That's it. Handy for robots and stuff, sign me up. Yeah, look at that. Right there. That is the gorgeous little product pick this week. Right there. That is my product pick this week. It is the DRV8871 DC Motor Driver Breakout. So this has everything you need on it. It can take anywhere from 3.6. Is that right? No. I'm getting my numbers mixed up. Yeah, it can take anywhere from 6.5 volts up to 45 volts DC through the terminal jack that you can solder on one of these. And then it'll output to your DC motor and you can control it just with two pins or even just one if you're only going in one direction of PWM control coming from your microcontroller. So let's see, let's take a look at some things here. First of all, there's the page right there. So go and check that out. Like I said, product ID 3190. So this can go up to 3.6 amps of current. By default, when it comes to you, it's set for two amps. So when it tries to draw more than two amps, it will shut down to save your batteries from getting chewed up. You can change out the resistance level of that little resistor you see on there. There's a little resistor on there that's a surface mount, but you can put on your own resistor to change the value of that current limiting. What else does it have? Thermal protection, so it gets too hot. It'll stop under voltage protection. And you don't need to give it any logic level voltage separate. So you can just feed it the DC voltage that it's gonna use for driving the motor and it'll sip off of that what it needs to drive the chip. You can use a 3.3 volt logic level microcontroller or a five volt logic level microcontroller. Those will work. And we have, we've got libraries in circuit Python. Or rather, I should say, you don't need libraries, right? You just need to be able to PWM. So anything that can PWM can tell this way to go. It is an H bridge driver, which means you can send the current flowing or the voltage flowing in either direction. So you can run forward and you can run reverse on your brushed DC motor. So this page here will give you some of those specs as well as there's a link in here to the learn guide. And so you can check this out right here. This will show you all of the basics of it, including the pinout. So you can see here on the pinout, there's the motor power pins. Those are broken out both as some little headers. So you can solder wires directly to that or to pins to put into your perma-proto or your breadboard. So you can feed it the voltage that's gonna be driving the motor there. Or, and I prefer this, use the included terminal blocks and feed it from there. You've also got your input pins. So input one and input two. And that'll just say if we PWM one of those up, we will drive in that direction. If we PWM the other one up, we'll drive in the opposite direction. And then there's that motor output pin. So what I thought I'd do is show you a little demo I put together of this in action. Let's jump to how about that view right there. And let me zoom out a bit. So let me give you a little tour here, in fact. So there you can see is my DRV8871. It has PWM pins and ground coming from this itsy-bitsy. It's a bit CRP2040. And then I have a DC jack plugged into a big battery pack. If I lift up my Lego contraption, you can see this is a large AA battery pack. You can feed that from a wall wart as well. Just for convenience, I'm using a battery pack. And then that is driving this motor that you see back here. And I've grafted onto that, one of our little Technic pin, Lego compatible Technic pin axles for the drive shaft. And we can focus on that. There we go. Let me move myself over to that side. There, you can see it a little better now. So there's the type of DC motor we're driving. There's my itsy-bitsy. Here is the DRV8871. It's driving the motor under there and we're getting DC power from battery. And then I have a little technical gear train there. So if I give this microcontroller power, it will start sending PWM to tell the motor to go in one direction, slow it down, and then go in the other direction. So this could be any type of hobby application. In this case, I'm driving some Lego without having to use sort of official Lego motors and microcontrollers and Blockly programming languages. Instead I just wanted to use CircuitPython. But you can of course use this for any type of small motor application up through up to a 45 volt motor that draws up to 3.6 amps. So it doesn't have to be tiny. So let's take a look at the code that I've got running on here. So in CircuitPython, I am simply, I'm just gonna pull the power. Pull the power from the motor there so it's not yelling at me. So I've simply got PWM IO imported into the microcontroller and then I've picked two pins, pin D7 and pin D9 are a good pair of PWM pins on the RP2040. So I'm setting up one as motor in one and the other is motor in two. And then you can tune the frequency here to something that works well. I found this 2600 after experimentation seemed to work pretty nicely as a PWM frequency. And then I've set a max value and that's at half duty cycle only because I don't wanna burn out the motor and I've got 12 volts of battery going into this so I don't wanna send the full range. So I'm doing about half range on the PWM to tell the driver to drive that about half that available voltage. And then in my main loop all I'm doing is setting my duty cycle on one pin to essentially be low as essentially the ground reference. And then the other pin I'm just ramping up you can see one unit at a time here it just ramps up to the max which is this 32768. Then we wait eight seconds that's why it's gonna run for a little while and then I slow it down so just run that same thing in reverse wait a second and then switch to other side. So if I give this power again it's been running this whole time. You can see it doing its thing there I'll go back to a full view see that doing its thing and there's our little driver board telling that motor what to do. All right, so pull that again let's see what more is there to say I think that covers it if you wanna get this for the discount price during the show all you gotta do is head to that URL right there, 3190 and take a look at the board right there. Now, this is a single motor it can drive in two directions but really it's a single motor it's gonna drive. So if you want to you can use multiple of these as long as you have PWM pins and I think there's probably 10 sets of them or something like that on the itsy bitsy you can drive a bunch of these just give them adequate power and then you can either set up a whole bunch of motors or you can set your timing to drive things like stepper motors one coil per so there are probably better drivers for that sort of thing but there's nothing to stop you from doing that. Let's see, questions. DJ Devin three asks over in our Discord can this be used with 130 hobby motors? I don't know which ones those are maybe a link I'm not sure. Yeah, these are the TT motors which are geared already and then I'm further gearing it down with the Lego there but these on their own if you look at the back of the demo here I have one of the since this has a shafts running through both sides of the body there you can see this one's spinning at full speed. So that's the full or rather half I guess half speed full safe speed on this motor is that there. I think the specs are in the product pages for the different motors that we have let's have the metal shaft versions of these and the bimetal if you take a look at this one here that's the one I'm using so this one's a three to six volt so lowest you can give it is three you'll hear it'll whine a little bit as we're ramping up until it hits that three volts where it can start moving and then further it'll go faster as it gets up to the six volts so this is one of the many that we have I think if you look up TT motor in our in the story you'll see we've got different gear ratios one in 90, one in 90, one in 90 this is a 200 RPM we've switched units here so I'm not sure which or which but any of those motors there are a great choice and you can also just drive these bog standard toy motors do we sell them on their own? Yeah this guy this little toy DC motor oh so that's a 130 size yeah yeah you found it for me thank you yeah so that's a typical I didn't know those were called 130s yeah so that's a pretty typical one that I tore out of every toy when I was a kid and was trying to see how it worked that's the motor you found I've got a drawer full of them in fact I just ran across so these guys with the little flat shaft you'll also find round ones we'll drive any of those because I think once I pulled out of VCRs or something like that okay so let's see I think that covers all the features on it the learn guide some of the motors that you can expect to drive with that and let me know if there's any other what a handsome little minifigures isn't that guy cute? in fact I wanted to show you that in the full full sort of twisted demo of this my little minifigure there is doing who knows what to this weird mad scientist guy I don't recommend torturing your toys so maybe this guy asked for it who knows is that weird? it's kind of weird but look at that guy you've ever seen a minifigure with a double tall head you're a weird guy is that actually his head or is it an add-on? yeah it's kind of his hat is another head oh my god that guy is weird okay also there's this cat right here okay that's enough playtime right so yeah this doesn't look safe I don't know what's happening it's all gone off the rails that's going to do it though so head on over here pick some up you can get them for the half price during the show right there they are $3.75 they are still in stock you get maximum of 10 per customer depending on what you want to do with them you might want a whole slew of them note these also have mounting holes so you can hook them up to your project a little more easily than I have with the Legos here alright that will do it so thanks everyone for stopping by and I will see you later in the week don't forget we have other shows coming up such as 3D printing Hangouts tomorrow morning and then we have Show and Tell and Ask an Engineer in the evening and I'll be back with a workshop show on Thursday and I might have even cleaned up some of this stuff by then so I will see you then thanks everyone for stopping by for 8 different industries I'm John Park this has been JP's product pick of the week