 And welcome to Just Lady Aida, Fourth of July weekend edition. That's right. Happy birthday, America. It's me, Lady Aida, and this is my desk where I fight the good fight, champion for America, capitalism, empire. Yeah. By the way... Motherhood motherhood. By the way, like jerks on social media, like we're a USA manufacturing company that makes electronics in the USA. So, how do you spin that? How is that bad? Good luck with that one. Do you have any other updates? No, just good luck with that one. Just good luck. Okay. Thanks to the... To the peanut gallery. Okay. So we've got some stuff on my desk. It's actually, I got, you know, there's a little bit of a thunderstorm today, so I got a bunch of work done. So let's start with this matrix portal. Talk about that first. So, go to the overhead. So one design, which, you know, it's actually like I've been meaning to send out for a bit now. And I finally wrapped up testing this weekend is this matrix portal S3. So the original matrix portal board used a SAMD51 with the ESP32 as a co-processor because at the time there was no such thing as the ESP32 S3. And if you wanted to drive like these LED matrices, you needed a lot of RAM and some fast chip and kind of the SAMD51 was the only thing that would do a good job with that. So I think even the RP2040 didn't exist yet. So the original version of this board, you know, this looked the same because it was actually the same package except it was a classic ESP32 room. And it had a SAMD51 and the SAMD51 talked over SPI to the ESP32 and would use that to do Wi-Fi and even Bluetooth connectivity. And like there's nothing wrong with using an ESP32 as a co-processor, but it does add complexity and of course slows things down. It would be great to do everything in just one chip. And the ESP32 S2 is also, I made a version with the S2. And that's okay, but the S3 has this really cool peripheral that can do like high speed, like bit banging. It's not PIO, it's like the 8-bit wide I2S peripheral, I think, which is also used for TFT. But it's great for driving these RGB matrices where you need to do a lot of like very fast bit banging. You know, you DMA out the pulse widths. So here we've got an ESP32 S3 and this one has 8 megabytes of flash and 2 megabytes of PSRAM. So it's got a little bit more flash because I want to have a lot of disk space on this. But the overall outline is actually the same. Like all of these holes and this, you know, stem up port and the stem IQT and the up down and reset buttons in the Neopixel and this button, they're all in the same location as the original Matrix Portal, SAMD-51. And, you know, we have a couple of SAMD-51 Matrix Portal. We have them in stock, but the ETA for getting more SAMD-51s is like 2024. And so I'm kind of slowly like, not immediately, but like kind of edging towards like, hey, let's just discontinue stuff with the SAMD-51 because it's just, I don't want to wait another year. I've had so much difficulty and the S3 is really price competitive. It's, you know, at the same price about three bucks per and you get the Wi-Fi. So you don't need like, again, two modules for it. So this and then the Pi Portals are also going to be redesigned. So this is my prototype. And I've got the header over here that plugs in and then I've got this SMT hex nut that I use to as a terminal block, you know, for these like spady connectors. And then, you know, this is running the, let's see, let me bring this, actually I'll hold this up. So this is running the SAM demo. So it looks much better on the main cam. And oh, there's also a accelerometer here. So that's how I'm using it to do the motion. And then I added one little thing. It's a light sensor. The original didn't have a light sensor, but it was so expensive. And I was like, oh, you know, maybe you want to see the ambient light and use that to turn on off stuff. So another nice thing is you can't break the S3. It's got a raw boot loader. It's just overall going to be, I think it's going to be less expensive and it's going to be like as fast or better. So that's the Matrix S3. And let's go to the computer and I'll show just quickly my Matrix portal. Sorry, one second. I can't go to high portals. And then, yeah, so I did the S2 version, but that didn't, that didn't end up getting made. So this is the Web-C. Later. The moment we turn on the, all the layers. Okay. So, okay. So you've got, you know, this nice still screen fill B made for me. One thing I changed, this is the Rev-B that I showed on the overhead. One thing I changed is. I'm actually going to have two SMT connectors. I'm going to have an IDC connector pointing up and then a 2x10 socket header pointing down. And so right now I have the socket header plugged in and that allows you to just plug directly to the back of the Matrix displays. And there's a standard pinout hub 75 is what it's called. But there are some times when you might want to mount this separately and then have a cable that connects from the driver to the Matrix portal to the LED panel. And so this is an IDC connector. So you can see the outline. So this will allow you to plug the cable in. So it's going to be kind of weird. It's going to be two SMT connectors. And it's going to look like they go through, but they actually are like just both sandwiching the PCB, but one plug in and one cable in. So, you know, it's good because it'll. One thing that people did say is okay, I don't want to have it plugged in directly. I want to have it mounted elsewhere so I can press the buttons. Get the level shifters to give you that three to five volts. This is the S3 module. We use every pin on here. Just nice. I still have a. All the, all these pins available to these GPIO. In addition to the, you know, the reset boot loader pin debug output. It's just the UART hardware, UART debug output. And then a bunch of GPIO, including, you know, basically five analog inputs and three-fold ground. Stem EQT, if you want to plug in sensors, you know, one project that was very, very popular with the matrix portal. I'm going to, you know, make sure that we can. We created is the CO2. This project from Carter was very, very popular, which allowed you to make a. You know, use the LED display to tell you how. But the air quality is like based on the CO2 readings with a common CO2. NDR sensor, the SCD 30 and was nice is that there was like no solder required. Just you plug it right in and then like, you know, it would read the sensor data and display it and particularly having. You know, this very simple to. Read and understand display was, was kind of nice. So one thing that we did after I did the revbies, I gave them to Melissa who did the matrix portal circuit Python library. And I said, hey, can you go through and just verify every single guide works? You know, even though this is now an ESP chip, not as Sandy 51 and she went through and tested every single guide. And fixed a couple of like typos and bugs in the meantime, but verified that they all work. So it's nice about Arduino and circuit Python is it's it's really easy. Like if your hardware changes underneath, it actually might be okay. The matrix portal library actually, you know, it's, it's Python and it just checks like what board am I running on and it changes the pins for you and it like kind of magically works. And then also added some mounting holes here so you can see these four mounting holes. Again, in case people want to mount this separately than the main board. So this is the first of the DCM D 50. It's like one of my favorite chips. But it's like working my heart too many times and this is time to let go. If I was a country music singer, I'd probably have like a song about it, but I don't I can't sing country. Okay, so let's go back to overhand. I'll show some other stuff I'm working on. Okay, so that's that one this one's done. So I'm actually I ordered PCBs to get this completed into the shop. So see it soon. I'll be cool. And then I also you guys maybe have seen this a couple desk of lady days ago. This is a QDPI BFF that has a three watt I2S amplifier chip. You can kind of barely see it underneath here. Such a nice overhead. There you go. I2S amplifier here and then also squeezed in a micro SD card slot so you can turn this into a little audio player that has digital output. One thing I made a mistake on you can see is the the LR clock, the word select clock and the bit clock for ESP 32 chips that can be any pin you can use any pins you want. And the RP 2040 you can almost use any pins, but the pins have to be consecutive in a certain way and I had them consecutively the long way. Like I think the LR clock was before the bit clock either bit clock for the hour clock or whatever. So not only do they have to be next to each other, but one has to come before and so I kind of just like cutting quickly soldered. I mean it's it's it's filthy. You can see I can cut the traces and wired them with a little wire wrap wire, but it works good enough. And then this is the RP 2040. So let's see if we can do a quick demo as a file audio clips on there and that's also working other than that I fixed it and now I then I just test it and to do my testing. I've got this bin called QPy and it's a bin with all of my QPys and BFFs and everything and so I you know I pulled them out to quickly test to make sure that it works with all of them. So I've got, you know, this is the S3 and I've got S2 and I've got the SAMD 21. The audio BFF won't work with the SAMD 21 because the I2S pins actually intersect with the SPI pins. But honestly, I wouldn't I would say hey instead of using the original SAMD 21, which is now a little bit long on the tooth update to the RP 2040. Here's another ESP classic. This one also sure works. I'll test this as well. One thing I did want to mention it's not out yet, but coming soon is a new QDPy S3 this time it's going to come with PSRAM. I forgot that the chip originally when I made the QDPy S3 it came with eight megabytes of flash because that was the only version available. Then they came out with a version of the chip that has PSRAM built in. So I made a PSRAM QDPy, which will be really good for Circuit Python. All right, so that that also got wrapped up today, which is wonderful. So put that aside. And then to the next thing I'm going to work on, which will lead into the great search is this is an RP 2040 Metro, which you can see because it's right in here. And I think I showed off the schematic, but finally I have the boards completed. So it's got your RP 2040 boot button, reset button, STEMI QT port, USB type C, micro SD in this spot here that is normally, you know, I put like a Wi-Fi something or other or some other accessory, but micro SD fits very nicely and it's always very handy. I did wire up the micro SD for SDIO, not just SPI like I picked there were enough pins that I was able to pick some pins that the SPI ports connected for like standard SPI SD card usage, but also SDIO and like I think the right order so you should be able to use one or the other. SDIO is not super well supported, but there is an example for it in the Pico SDK. So that'll be kind of interesting if you want like maybe super high speed micro SD card reading and SWD port. And then I also put in the standard, you know, Pico debug port, which is an SWD but over this like three pin connector on a switch for the DC jack and of course five volt three volt regulator and SPI port. And this is kind of funky. I think I mentioned this before. Normally, you know, the pins on Arduino or Metro, you know, this compatible layout is D0, D1, D2, and you see like from D2 it goes up to D13 in order and that's like super cool and everything. But also D0 and D1 are used for the hardware you are, but the way the RP2040 works is you can't pick any pins for hardware you are. They have to be a certain subset of pins. There's a lot of them, but you can't just pick any like pins. So zero and one can be UART, but it's the opposite way of how most Arduino or Metro boards are wired. I think like normally, yeah, normally TX is D0 and RX is D1. And so I have a switch here and you can flip these two pins around. So either you get numerical order 0, 1, 2, 3, or you get like logical order where you get the UART in the order that you expect with RX and TX. But also maybe handy if you wire something and you're like, oh no, I wired the UART wrong, just like flip the switch. I love it. I think everything with UART should come with a little DPDT switch, just like swap it around. So I actually sent one of these out to a couple of remote engineer folks, creative engineers, and they actually tested it so far. So I'm going to do a last pass, just check all the GPIO, check that the USB is wired correctly, the microSD. You know, do some, make sure that DC jack is going to work in various voltages and all the SWD ports and everything. Oh, there's also a neopixel here that I didn't solder in. But, and then of course we'll do a nice silk screen for it. So now we can go to the great search. So, great search brought to you by Digikey and interviewed every single week. Lady of User Power of Engineering, help you find things on digikey.com. Lady of what is the great search of the week this week? I'm glad you asked. This week's great search is we're going to look for some 2.1 millimeter DC jacks. This is going to be overhead and I'll show my design and the part I picked. I'm focusing, focusing. Stay on target. So, this Metro RP 2040 prototype that I'm working on, one thing I really like about this shape, this is kind of the classic Arduino shape, which I call Metro because I don't want to use the word Arduino, it means something. But for those boards, which I really like, they're kind of nice and big and one of the side effects of having plenty of space is that you can have a lot of accessories. So, not only do you use USB type C or micro B for power and data, and there's a reset switch into the micro SD card slot, but you could also have a DC jack. And, you know, even though a lot of things plug into USB these days, like almost every device I buy these days has a USB port for charging. There are times when having a DC jack is really handy. These DC jacks can provide up to 12, 24 volts. They can do five amps. Yeah, USB-C can do that as well, but it's often easier to get a DC power supply that you have handy. And then that voltage ends up out here on the VN pen. And so if you want to use it for powering motors or steppers or LED strips or solenoids, or actually a lot of industrial equipment uses 12 volts. So, you know, if you need 12 volt DC, yes, you could make this USB-C do power delivery and get 12 volts, but it's easier to just have a dedicated non-power delivery port here that you know I'm going to give you, you know, nine or 12 volts DC. So let's go to the computer. I'll show some other stuff that at least at Eight of Fruit Wee Stock that uses the same size. So this is, you know, an example of, you know, the DC jack with a switch built in. But you see it uses this kind of standard barrel connector used in, you know, there's a lot of different sizes for barrel connectors. There's 5.5 millimeter outer, 2.5 inner, four outer, 1.3 inner. But the most common that you see these days is 5.5 outer diameter. That's the diameter of this jack is 5.5 millimeter. And the inner diameter of the little nubbin that sticks out, that's 2.1 millimeter diameter. So see, we have a lot of, you know, adapters and plugs and cables. And if you look at, you know, we have a 12 volts, 12 volt one amp power supply. This also has the same 5.5 slash 2.1. So, you know, a very standard connector. And, you know, yes, I've been doing some magical future. We'll all be using USB power delivery. But yeah, at least another decade of this stuff. So if we want to use these sort of power adapters, we'll need to get a DC jack. And there's a couple of things I've learned about using these DC jacks. So I'll show you what I've learned because this is, you know, before USB, this is kind of the standard. If you look on electronics from like, you know, the 70s and 80s, you know, basically once they started not using mains power directly with devices, they went straight to wall warts or power adapters. This is the standard connector. So let's look for DC jacks. And there's a couple of things. So there's cables. So if you want cable assemblies, this is one category. But what we want, and you can actually see this is a inline adapter, but we want something that goes into a PCB. So let's go. Oh, and also if you want, of course, power adapters that this goes with, you know, did you key stocks every voltage current? Well, that's weird. It goes the opposite direction. Usually, oh, because I typed in jack. If I typed in plug, it would have plug versions. So I was like, why is it the opposite polarity? This is here you go like this one. So you see this is this very standard wall adapter you plug it in and they come, they come in different versions also that are that come with, you know, European, Australian, US, Japan, et cetera. Different voltages. This one's 12 volts, 12 watts, but they go up to 24 volts easily. So let's say, let's look at some of the voltage outputs. There's some adjustable voltages, but it's not too, you can get up to, I think 24 volts DC. You need a high voltage. You're not going to get 24 volts out of USB power delivery. So also it's maybe a little bit less expensive because you're not dealing with the overhead of USB type C, which needs its own like big power plug. So let's, so I go back and look at again DC jacks. So under barrel power connectors, barrel type, you know, because it's round and thin and circular and has a hole in the middle. So it's called a barrel type. So let's just look at all the power connectors and take a look. So there are tons of these. So this one you can see here, it's 3.4 by 1.3 millimeter. This one is 5.5 by 1 millimeter. So this is a SMT version. This is a 2.35 by 0.7. It's smaller. I don't, I'm not a huge fan of these, but I will say that this size is very popular on USB hubs. If you want to have optional external 5 volt power, you know, because these are a little chunky. These are available. You can see this as a through hole style. Another through hole kind of narrow SMT a little lower. This one is SMT, but it's pointing straight up. Which is kind of cool. This one is like to the side. So, you know, different orientations and stuff. So first up, let's just go and look only for the active and in stock, I picked in stock items just to, just to pair down to the ones that we want. We want a jack, not a plug. I will say that trying to use female or male gets very confusing because it's like, there's, you know, which is the gender. It's very, it's unclear. So I would not use the word male female when trying to differentiate between what plugs in and what gets plugged into instead use plug and jack. Jack is the thing that you plug into and plug is the thing that, you know, is plugged. So especially when you're dealing with connectors that have like multiple like sinusoidal connections and inputs and outputs. So we want a jack because we want something that it gets plugged into a plug is what comes out of the wall. And now this is kind of like the thing that engineers have to deal with. There's what it's called. And then there's what it is. So we call it 5.5 millimeter diameter, 2.1 millimeter inner, but that's not actually the measurements. The measurements can actually be two to 2.05. So let's just look if we just filter on 515 millimeter out of diameter, you'll see that first up there is like funky 1.6 millimeter. These are on. And then there's also the 2.5 and 2.5 fives. So there is a variant of this jack that looks like identical except the inner pin is a little bit wider. And that means that it can carry a little bit more current. So technically you're not really supposed to take more than I think 60 Watts, maybe five amps over a 5.5 millimeter 2.1 millimeter jack and plug. So if you want more wattage, you have like a monitor or computer, like something that needs 100 Watts, you're supposed to use 5.5 slash 2.5 millimeter. Whether people do or not, I mean, sometimes they do, sometimes they don't, sometimes they go to another connector. But you'll definitely want to make sure, you know, you can, if you plug a 2.5 inner diameter plug into a 2.1 millimeter jack, you won't get power coming through. It'll look like it's plugged, but like the thing won't turn on because the pin, it doesn't, isn't touching the cup. And if you're using a 2.1 millimeter jack and a 2.5 millimeter jack and 2.1 millimeter plug, it won't plug in. Like you'll try and it will like, it's like, you no matter how much you force it, it's not going to go in because it's, it's 0.5 millimeter too big. There are once in a while jacks that can do either by using like a little bit of spring and it's 2.1 millimeter, but it pushes the pin up. So like even if you have 2.5 millimeter plug, it will still fit. Just pick one or the other. I don't like to play these games where it's like you can kind of make it work. So in which case we're going to go for 2.0, 2.05 and 2.1. So there's a little bit of variation. It's basically all the same. And we're going to skip these. Wow, there's even a 3 millimeter. So like again, totally non-standard, but it looks to the human eye, it looks the same, but it won't plug in. Okay, next up. So there's a couple of different versions. There's the SMT and through-hole. I have used SMT. The SMT is actually fairly strong. I'm not using it on my design. They tend to be a little bit more expensive usually, but you would also definitely need to have really big pads. You know, I don't know. Let me see. I think our solar, I think one of our solar chargers uses SMT. Yes, this is the SMT. I've used it. It works. It's not as mechanically strong, of course. And especially because again, people might try to plug in the wrong side, they can actually put quite a bit of force on that connector. If you do go with SMT, make sure you get the kind with these nubs that help, like they point, they stick through the circuit board and they give you mechanical strength because this is not just, this connector is not only electrical, but it's mechanical. And it's a very, very common thing that the DC jack is what cracks off and the thing stops working because it's easy to torque it or you've got the plug plugged in and the plug, you know, it gets kind of large and chunky and it's a great lever, you know, and your device falls off, the cable gets strung up, it pulls and it yanks and it yanks it out. So I, you know, for this design, it's a little, it's a little breakout board. It's an older design. It's okay. You can do it, but if you're going into production, you're manufacturing something that's going to be used by people in their homes often or by folks who might be a little bit rough. I would not go with the surface mount. I would go with the through-hole. So let's select, not panel mount, let's do through-hole and then there's through-hole and there's through-hole right angle because there's the ones that stick up. I've personally never used the ones that stick up, but like they're very cool and I'm sure they work just fine and if your design happens to need the power going up, you know, more power to you. Do note you can, sorry, for through-hole there's also, so these are the jelly bean. They're almost all the same. They look, they have these three pins. So inside is a switch and the switch, so the three pins where you're like, oh, there's only two pins on the contact. There's a switch here that is normally closed and when you plug it in, the third pin disconnects from the second pin and you can do that to have like an internal, like first we can detect whether, you know, something got plugged in or you can use it to switch out to a battery power. However, there's one thing you got to watch out for, which is that the thing that switched is the ground, not the power, which means that there might be another path to ground somewhere or somehow and so you'll notice that pedals, guitar pedals used by musicians have center negative so that this is switching the positive pin. However, nobody else in the world does that. Everybody else in the known universe uses center positive. Which is what you're almost always going to encounter. So stick to center positive and then if you want, you can use the switch, but just remember it switches the ground out, not the positive pin, which is, you might have to think about your grounds and your earth grounds, make sure that there isn't another path through where you might be surprised when your battery shorts to your power adapter. Okay, one more thing, there's these thin pin style. Again, I'm not a huge fan of it. I feel like if you're going to go for it, go for the large chunky pins because you want a mechanical connection, not just electrical connection. However, side note, these do plug into breadboards. They plug in quite nicely. So if you're having to solder this into a perf board or a breadboard or something else, it's a point one inch spacing. This actually ends up working out quite nicely and the pins go right through the holes. We don't want that though. We want something with chunky pins. Another thing to watch out for is they're not all rated for the same amount of current and voltage. Some are rated for 2.5 amps, some for five, some for 24 volts, some for 48 volts, some just for 12. So they're all kind of the same build, but you know, the rating is the rating. So you should probably obey the rating. Wow, this one goes up to 10 amps. This is, oh, this is kind of a nice, ooh, look at that one. It's got like all those contacts. This is very nice, but it's a little bit more expensive. Almost four bucks. So let's, let's talk by price and then we'll just see what's up. You know, I don't want the vertical. So let me change the mounting type and I'm going to get rid of, I want right angle. Yes, I'm going to get rid of through hole so that I only do the right angle. This one's pretty good. Let's see, but maybe I want the five amp version. So I think this one's kind of nice and I like it's got the big, uh, chunky pins. Oh wait, this one doesn't have the switch. Never mind. Hold on. That changed my mind. I'm going to go for the version with a switch. Single switch, normally closed. Because I actually like, even though, again, even though I don't use the switch, I like the mechanical connection. Okay. Back here. Let's see. This one, five amps. This one's good. Okay. This one. I like this one. It's got the pins. Nice thick pins. Uh, standard layout. It's got the kinked pins. So, you know, when you, when you solder it in, it stays in place. Don't forget, you'll need plated slots on your PCB, uh, to make sure that these fit in nicely. Oh, you can also use big round holes. It just makes it a little tougher to fill it with solder. Um, so I use plated slots just to check out your CAD program on how to create plated slots. All right. So if you need, can have your generic 2.1 millimeter, 5.5 millimeter DC jack that can do up to five amps up to 20 volts. This one's pretty good. I'm going with this one. That's GCT DCJ 200. It's my pack, The Great Church. That's Great Church. Oh, kind of key. Thanks for joining us this sort of holiday weekend. Thank you so much everybody we do on our shows and more all throughout the week, lots of surprises. And uh, only in America could something like aid fruit happen and someone like Lemore do it. So, you know, we've got a problems. but it's better than the alternatives. Yeah, and I mean that is our country, not as us. Okay. All right. This is the least worst thing going on. It's not so bad. It could be worse. It's not so bad. Okay. All right, everybody. Thanks so much. Thanks so much. We'll steal here. That's your desk of Lady Eda. Don't blow your fingers off this week.