 and welcome to Disco Lady Aida. Hi everybody, it's me, Lady Aida, at my desk. Happy weekend. We got a whole bunch of hardware done. We're gonna follow up on last week's videos where we talked about our Feather RP2040 series. So last week we did the RFM69 and the DVI Feather. And the DVI Feather is actually gonna be in the shop really soon, which is cool because people can do all sorts of video projects. And then we got some more prototypes this week. So let's show what the particular prototypes look like under the overhead. So first up is, hold on. This is a e-ink Feather. So it's got the RP2040 bones over here. They are RP2040 chip, lipo battery and battery charging, USB-C reset and boot buttons, Stemi-QT connector, and then over here is a 24-pin connector and some power supply stuff you can see, like the little inductor and some transistors and capacitors and stuff to support driving e-ink displays. And we have a bunch of e-ink displays stocked. The small is 1.54 inch up to, you know, they make them huge, they make them up to seven inches or more. This is a seven-color e-ink display. It's called an ASAP display. As you can see, there's like red, blue, dark blue, you know, white and there's also black over here. So this doesn't even show all the colors, but there's, this is a seven-color e-ink and this is also supported. One of the things about e-ink displays, because first off it's, they're quite a thing. You know, I don't recommend writing drivers for them. I've written like dozens of drivers and it's, you know, they're all very similar, but if you don't get the driver perfectly right, you don't respond, because the commands are slightly different from chipset to chipset and the chipsets change constantly. So this one is a tricolor. As you can see, there's a red layer and a black layer and white is just like the absence of any layers. Even if there's like a two layer, it's called a tricolor. So whatever, because white is always like one color. And these displays, like this one I think is, oh man, I can't remember, it's like 220, 250 by 120 or something pixels and it's one bit per pixel per layer and each layer is like considered its own frame buffer. And they do end up needing a lot of RAM. Like if you do the math, you know, like for example, this, let me just quickly pull up the part number so I can tell you what this is. This is the 2.13 inch tricolor. Oops, sorry. Tricolor. Sorry, it's 250 by 122. So you do the math, 250 times 122 is 30,500 pixels and there's eight pixels per byte. So you need basically like 4K of RAM for each layer that you have of this display. So together it's 8K. And you know, basically you can use the external SRAM chip and we've done that for some of our feather wings but it's much, much faster if you can just buffer the whole display in the chip RAM. But 8K is like, you know, if you have a Arduino at mega 328, you only has 2K of RAM. And so an RP2040 is a great chip for this because one of the cool things about the RP2040 is it has 264K of RAM so it can easily buffer this entire display and draw it. And of course, you know, it's ink. So after you're done playing with it, you just connect it. And even if the RP2040 isn't designed for low power, it does do a fair job. And I'm gonna test out just making sure like what is the power draw. So I'll do that before ordering this board just in case I made a mistake. So that's the ink feather. And you know, I kind of pulled the connector back. You can see that I wanted to make it so that the mounting holes were still usable. So like it's kind of positioned it. So the flex connector is not in the way of the holes. So this ink feather, I'm gonna do a couple more power tests but it does work quite well. And it works with our Adafruit EPD Think Ink library. And we have drivers for all sorts of chipsets in there. And then the other feather that we got, the RP2040 feather, because we've been designing a whole bunch, carefully put the ink stuff away, is this one's very exciting. So this is USB host. Sorry, one second. This one is USB host feather. So again, RP2040 same circuitry. And you'll notice, you know, one of the nice things about the bones design is that this part is all the same and then we just change around what's on the end there. So it's in the ink. This one has a surface mount USB A connector. On a previous great search we showed how to get this connector. And it just makes it easier to less through hole soldering and also makes the bottom nice and flat. And then over here, this is a TPS 61023, which is a, you know, one amp five volt boost converter. And that's great because even though this is, you know, cut through USB and this gives you five volts, maybe you want to wind this off of a LiPo battery. So let me find my battery. Hold on. It was here. Uh-oh. One moment. Where'd it go? I had a little power monitor, but it's black and everything on my desk is black. So I'm not gonna find it, but you can connect a little power monitor to here. And I just verified that it gives you five volts output. And then I even charged a phone through it to make sure that I could get a half an amp, which is the USB spec. And even down here, you can see the little five volt fuse even since five on it. So that gives you 500 milliamps at five volts. And this is great because, you know, you can turn on and off. It's very important I found that when you're doing USB host stuff, to be able to turn on and off the USB power, so that the enable pin is like a true shut off. So that will completely de-power the five volts. So that kind of gives you a fresh start, especially when like you have chips that are kind of like non-numerating cleanly. You know, you can start it with it powered off, turn it on and then wait for the enumeration. And so here's, you know, an example of an HID device. So this now works with teeny USB and we have, what I like is of course, you could do USB host through the main USB port, but then it's really hard to debug. So what I like about having the USB host be separate is now you have debugging and programming through here and your peripherals there. So let's plug in this SNES like joypad and then let's go to the computer. And I'm running this example that does an HID report and we have to configure it to tell it, you know, which is the data plus pan and then data minus is always one pan after that. That's how it's done the PIO. And then the enable pan again to enable the V bus. And then you just have the USB host code. We wait until the serial ports open and then the second core is where it does the USB host stuff. There's a couple of requirements like you have to be running in 120 megahertz or 240, which is overclocking because that gives you a nice clean divisor into the 12 megahertz. You know, probably it couldn't eventually be tweaked. So it didn't have to be so specific, but it's such not a big deal to compile it with that frequency. And then what this does is it, you know, on mount on when the device is plugged in, it says, hey, here's a VID and PID. So detects what device is plugged in and then it listens for HID reports. So HID human interface device is a USB standard for keyboards and mice. And like it basically what allows you to have a USB keyboard work with any computer like mass storage, it's a universal and then this joystick is also an HID device. So I think I have the right comport. So now, let me reset just to make sure. Just to make sure. And then I have like a bazillion comports. I want 13. Okay. So it's streaming out the HID report. I think if I go to the top, yeah, so it boots up and it says, you know, plug in a thing. And now as I press the buttons on this little joystick, you'll see the data changes. So it's like 1F, 0F, 8F, different buttons connect to different parts of the HID report. And like I said, keyboards and mice are standard. I think this is probably a generic joystick. But this is useful for HID remapping. So a couple of projects that we thought would be neat to do is one is this idea of an anti-shake mice. So if you have an essential tremor or you have like Parkinson's and you shake uncontrollably, it can be very hard to use a mouse and like the harder you concentrate, the harder it is. And so your mouse shakes back and forth. Well, that's like, if you have an HID remapper, you can read that mouse movement data, I apply a low pass filter. So instead of it shaking around a lot, it, you know, slowly moves, but it moves in the average of like the last 20 data points. So that's kind of a cool project that you can do with HID remapping. And another project you can do is get an IntelliQey is working. So this is an IntelliQey, maybe we can go to just me because this is kind of big. I can hold this up. It won't fit on the overhead. So this is an IntelliQey. So this is a accessibility board. So this is like a touch screen, a touch pad on a screen. Probably resistive underneath. This was like designed in like 2000s or 90s. And it uses USB. And you'd think like, oh, you know, you have these overlays. Show the overlays real fast before we move on to the great search. But there's something really neat. Sorry, one second. So it comes with these overlays. And there's a protector to put aside. And like each overlay has, like this is a mouse overlay. So you can see it's like, you can move the mouse around. And then this is like a web browsing overlay. So it has like command and www and .com. So it's kind of like, you know, and it has a little bit of a mouse. This is like you can have quick access to common web browsing things. I remember like, you know, we talked to Bill Binko about accessibility. He's like, if you can get people connected to a web browser, everything else is easy. Like the web browser is the hardest part. But then from then on, you can do anything through a web browser. And this is just like a plain keyboard. And then what's really neat is when you insert this overlay into the slots, there's a slot up here. So you put the overlay in and it automatically knows which overlay and it converts into this kind of keyboard. So, you know, if I plug this in and I pressed on the D, it would be D. Whereas if I had like this calculator overlay, that D would be, you know, six. And when I pressed it, it would know that I was pressing six. How does it know? I'm glad you asked. It's a very cute idea. So over here on the left, you see that there's this like black marking and each overlay has the black marking, but they have it in a slightly different location. So, you know, this one is closer. So like this one has like one marking here and then this one has three and this one has two and then this has two, but they're in like a different spot. So there's three photo cells and the photo cells are looking for light or dark, like whether they can shine light through the paper or whether the light reflects back and that's how it knows which overlay. And so it has like inside it has the brains to know like, oh, you put in the mouse overlay, I'm gonna act like a mouse now or like you put in the, you know, the calculator overlay and I'm gonna act like a calculator. This is really, you know, great accessibility board. It's like really adorable. Of course, it's designed to handle spills and drops and it's really nicely designed. There's only one issue which is that the chip that this uses is called the Cypress Easy USB, which I like to tell people is the first chip I ever programmed for. When I got my first gig at a school at Mitsubishi Electric Research Lab, it's only a summer job. I programmed a Cypress Easy USB and what's really interesting about this chip is I guess at the time, flash memory was really expensive. And so what they did is the chip had RAM, but no flash. So the chip would connect to your computer and say, hi, I'm a new Easy USB chip. Give me your firmware. And the computer would transmit the firmware. Like it's kind of like a dynamic, it's like a bootloader, but it bootloads every single time on connect. It bootloads down the firmware and then it restarts and runs that firmware. And so, you know, on one hand, this is kind of cool if you wanna have like firmware that's constantly updating because the new driver has a new firmware. But the downside is it doesn't act like an HID keyboard. This isn't a standard keyboard because it needs to have that firmware downloaded to it. And so, you know, on a computer, like a Windows computer, you know, it's not too big of a deal because the company, they no longer make these, but they open source the driver and so you can recompile it for Windows 10. But if you're on Android or Chrome or iOS, you're like shit a luck because there's no Cypress Easy USB firmware downloader for iOS and there never will be because Cypress doesn't, you know, they don't support the stuff anymore. But maybe with this USB feather wing, sorry, it's just USB feather, we would plug in the USB from the Cypress into here and then the RP2040 would download the firmware into it and then it would just translate, you know, it would do that beginning part where enumerates downloads the firmware and then disconnects and then it would just pass through the keyboard part. So that will be kind of interesting to see whether we can get that working. There's existing code for the Teen C36, but again, the Teen C36 you can't get anymore. So, future adventure. So I know I went on a little bit, but I wanted to show some of the cool hardware. So, TAC who's the developer of Teen USB, we sent him an IntelliKeys. I needed to get one of our USB host feathers and working on it and we sent him like a trace from a Beagle that's connecting and there's existing code. So I'm pretty optimistic and what's nice is that, you know, this is one piece. It's, you know, all assembled, ready to go. There's no like soldering and with the built-in RP2040 round bootloader, it'll be very easy for people to update if like we, people make better firmware in Arduino for the USB host feather. So that's what we're doing over at my desk. You can tell it's extremely busy. So I thought we would go into the great search next. Here we go. Where in the world is the great search with DigiKeys? The great search brought to you by DigiKeys. I forgot to give you DigiKeys. Every single weekly data user power of engineering to help you. Yes, you find the things on digikey.com. Lady data, what are you looking for this week? I'm glad you asked. So last week, we talked about UFL to SMA adapters because we've got this RFM feather and actually let me pull up the design. One second. People can see how many folders I have on my computer. Okay, RFM. Okay, so let's go to the computer and I'll show off the design. Hold on, waiting for Eagle CAD to load up. You can do it. Eagle CAD, my computer. I replaced the fan on my computer so it should be a little faster. Let me slow it down. Okay, so this is the RFM feather. And if you all remember last week, we talked about this design. So this is a UFL connector. Let me put it on the T-DockU so you can see. One second. There's so many layers. Okay, so this is the antenna using the UFL connector. UFL connectors allow quick attachment to a tiny surface mount component and then it would go to an SMA connector. And so last week on The Great Search, we talked about UFL to SMA adapters, SMA versus RP-SMA. But now it's time to actually get an antenna. And I had, oh, hold on, let me get my ginormous antenna because people like this ginormous antenna. So I've got a couple antennas. Okay, so we've got this ginormous antenna here and then I've got attached to a UFL adapter. And what I like about this antenna is it's got this tilt and swivel. So it can be sticking up or it can be tilting to the right or it can be tilted angularly, like 45 degrees. There's a little clicker there. This is a antenna that is not tilt and swivel. It's just like, it goes on the top. Here's another tilt and swivel. This one is, I don't know what this is. I think this is a Wi-Fi antenna. So this is common. If people get routers, you have a little Wi-Fi antenna sticking out. Again, you could have it be 45, 90 degrees or straight out. And so, yeah, in this antenna, which is this enormous Lora WAN antenna, I thought I'd show how to find antennas because you can get any kind of antenna on Digikey. They stock thousands and thousands of different ones. So maybe show people what to look for and some of the specifications when getting antennas. So let's go to Digikey. Okay, so let's look for, let's just type an antenna. Let's start with that. And then last week, remember, we did the coaxial cables or the RF accessories. So this is like, even the image, even the, is the thing that we want. Well, like, yeah, I want a UFO to our, you know, SMA or PSMA adapter, but we want a RF antenna. So let's look for a single band and we're going to look for a antenna. Okay, so active as well. So let's start with that. And then there's like so many specifications to look for, but the first thing we want to do is like, okay, we want the frequency band. So we're going to be finding an antenna that's used for Lora or a packet radio in the 915 megahertz ISM band. And that's in the US in Japan, I think it's 868. And in parts of Europe, it's 433, very similar, but let's just do, you know, 900 megahertz for us. So there's a couple of, you know, there's a couple of places actually where you can do the frequency. You can do the center, the frequency group, but actually like frequency range, because I can get, you know, the 10 of the range is like, I'm generalizing a lot here because again, there's 1000, 1000 of antennas, but in general, you want kind of like a tight range around 900, so maybe like 850 to 950 megahertz. So let's go down here. Okay, so a lot of options. So like I said, you know, if you're in Japan, you might want 868. Let's kind of like just pick out a bunch that go from like about 870 and are at least 900 and 15, 920, 960, 950, 925, because it's, you know, you don't need to be too specific. You want to have a range of options. 915, there's a lot. And I'm just option clicking all of these. And 900, keep going, keep going, keep going. Okay, and now we're actually kind of getting to the end because this is past 915. Okay, so let's apply. And let's also only look for ones that are in stock right now. Like, there's a lot of options. So there's actually some antennas that already have a UFL connector. And like these are actually pretty good. Like if it's inside of an enclosure, again, this isn't weatherproof, but inside an enclosure, this is a perfectly good antenna. So a couple of those, this is like a whip antenna. Some of these are like pretty huge, just like a metal gigantic antenna. You're gonna have some high gain antennas. What we want and some surface mount antennas, what we want is a, and this is called a whip antenna because you can whip it through the air, I guess, I don't know. And we want, it's like a tilt swivel whip. So go to whip and we want whip, tilt and swivel. There are other antennas. The basic trade-offs you're gonna get with antennas without going into, you know, five years of antenna education, which I don't have is there's directionality and the matchingness of the game, of the gain. So directionality is actually called the gain of the antenna. Now I just wanna warn people, because if you're like an analog engineer, you'll be like, oh, the gain of a circuit is how much it amplifies. These antennas are not active antennas, unless you're purchasing an active antenna. The gain isn't, like it doesn't give you more, it just means how much more directional it is. So if you're doing a project where you're trying to, you know, you have an antenna and you're pointing it at like the moon or you're pointing it at another building or you're pointing it at, you know, a warehouse or something and you want to transfer data back and forth, you want a high gain antenna because you want to be able to reach that just in that one direction. So it's high gain. If you are just trying to like radiate and get data from all over the place because you have like a mesh network or you don't know where the nodes are or you're doing like a Laura setup where your nodes could be traveling all around, you want a low gain antenna and the lowest gain is one because it's like a unit circle. And then the matchingness of the antenna is the VSWR and that it's like the something virtual standing wave ratio, I think. I don't remember the V stands for. Basically you want it as low as possible, the lower the number and basically you're going to get like two or less that's normal is how efficient the antenna is at converting the electrical into RF energy. I, again, I can't get into a huge antenna tutorial right now. There's lots of good videos online on YouTube. Okay, so let's pick something with like a VSWR of two or less. Again, that's considered good. Other than that, in general, and then the gain, remember the gain is how directional it is. It's not how much more power you're getting. And then we have a lot of good options. So I do like, you know, there's really long ones and there's short ones. A lot of options here actually, which is kind of good. This one's nice. I kind of want like a huge one, which would be kind of cool. So, you know, I could do by price. You can see what's going on here. This one's kind of short. This one is like this, this length. This one is so long, but this one looks good. I think this one is kind of the nice one because I want like a nice big antenna because what I'm going to do is I'm going to use this antenna to do range testing. I want to see like how far can we go with this Laura or RFM packet radio. So this one is my pick, the ANT916OCLG and this is by Lynx. And like I've been using Lynx antennas since like college in there. They've always been really good. They're very reliable and they've got excellent data sheets, which tell you like they'll give you the VSWR and they'll give you specifications and they're very reliable. So I think this is going to be my pick, 10 bucks. Good, very good. That's a great search. That's a great search. Where in the world is that part I need? The great search. And that's our show first now. We got a lot going on. So we're going to make this super fast half an hour or so. We'll see everybody all throughout the week. Lots of stuff. We've been posting up tons of videos. It is a hardware bonanza. Join in, join up, share and we'll see you later on in a week. All right. Bye everybody. Bye everybody.