 And welcome to the Descalady Aida. Hey everybody and a happy day light saving Sunday to all y'all. If you're not watching the Grammys, you're here with us, Descalady Aida. We're doing some engineering and sometimes we do sing, although I don't think I want a Grammy for my singing. That said, we do have some discounts going on right now. If you want to pick up some components, maybe a Raspberry Pi for Pi Day for a song and a half. We've got a 10% off discount code, use the code Pi Day. It's running until the end of today, I think after that. It's off. Yeah, so you have two hours. You have a couple hours. Yeah. Pi Day. Yeah, and celebrating on Pi Day, let's just jump right in because this is on my screen. How is this possible? The head of Ebon. I know. Well, this is a little demo for the Raspberry Pi Pico, the RP2040, this is the nightmare. The RP2040 chip, well, we actually, don't forget DigiKey had a live stream today with Samantha from Pi Foundation, Sean from DigiKey, Mike from Make, JP and Kirk from SparkFun, CTO, and they talked about the RP2040 and I put together a DVI breakout. So you want to pop up on the overhead real fast and I'll show what the magic is. This is the RP2040 Pico board and connecting to three, sorry, four sets of wires. We've got clock, yeah, clock, TX0, TX1, TX2, so three differential pairs and one differential clock with plenty of grounds in between to this DVI breakout and that's, it's HDMI, but like we call it DVI probably just because we don't have to pay the HDMI licensing fee. So it's a DVI breakout and all it does is basically give you those pins in a row so that you can use this, you know, standard connector. If I unplug this, will it break everything? Let's see what happens when you unplug it, it'd be super fun. I'm going to unplug it. Thank, Don. Nothing. It's gone. It's the nothingness. So it's got that standard connector that y'all know and love and yeah, when you plug it in, you get DVI output and I think they got like up to like 4K or 2K video. I don't think they have audio going over the video, but the audio could be separately over I2S. This is a little breakout I put together and it works fine. More proof that, you know, people will say like, oh, you have to be really careful with your routing with like DVI and stuff. I'm like, well, you know, you can actually do it on a slaughterhouse breadboard, which is, you know, a crime, but the differential signals are very durable. They'll put up with a lot of abuse. So this works great and I think it would be fun. You could get video games going on a RP2040, maybe wire up like a Wii controller or like a SNES controller and maybe play some arcade games or emulators. It's just fun that you can do this all on a Cortex M0 using PIO. How fun is that? It's really fun. Yeah. And I think, you know, sometimes in, so the maker and Hopi's community, we're the ones that are pushing the boundaries. We're overclocking. We're doing all sorts of stuff. And I think everyone should celebrate that. Yeah. And be like, you know, don't do that, police. Be the... This is hacky. This is cool. You want cool hacky stuff because all the cool hacky stuff is what pushes the state of the art. That's what we're trying to do here. It's cool. It's hacky. It's cool and hacky. So I thought, you know, this is neat. I'm going to have this break out because I thought it was actually really useful. There's always times when I need to do DVI, HDMI stuff, but I'm also thinking now maybe making like a feather wing for the RP2040 feather so you could plug it in and get maybe I2S audio out and HDMI DVI out and then maybe like an edge connector for connecting like a nunchucky board. I don't know. I'm still thinking about it. But that's... So that's my first demo. It says DVI breakout. Thank you for that. I'm going to unplug this, okay? Yeah. It did nothing. Everything worked out. Yeah. I'm going to make sure. I'm going to do one. Second, we talked I think a week or two ago about mechanical keys. So I think I showed off, you know, this is a Kato key with a small key cap. It's a mechanical key and there are these cool sockets you can get. I made a breakout for a socket. Let me see. Can I zoom in on this one? No. I have to actually manually move it, huh? Okay. Do it again. Do it again? You can do it? No. Yeah. Okay. Whatever. So this little breakout, this is a socket for one of the switches and if you put the holes in the right location, this switch clicks in. So you can see like here profile and then this is the switch going into the PCB and it goes through the PCB and into the socket and so it clips into these two pins and then you can see the positioning hole in the center and actually works pretty well. There's also a slot in this switch for an LED. You can use like a through hole LED if it goes all the way up or if it's very small like a 1.8 millimeter LED or you can use an RGB LED. So remember I talked about those through hole, sorry, not through hole, there's surface mount, reverse mount, neopixels. So I did that. The only thing is I am of course got to reverse mount upside down, right? Like I didn't flip the pins properly to do the reverse mount. So I did fix it on this little breakout over here by, well, you know, just being a little creative, but it works fine. So this is the breakout showing like the neopixel you see sticking up here and then when you attach the switch, it comes out through and illuminates the key cap. I did make this a little bit bigger right now, it's exactly the same size as a key but it turns out you can't connect to these headers over here because the switch is like in the way. So I extended this out by 0.1 inch just to give it a little bit more height. So it doesn't tile perfectly on the 0.75 inch boundary but it's a trade-off, it's just a little breakout so I'm going to make it really easy to use as mechanical keycaps. And I also, let me go back out, I also designed a feather wing. So the feather wing holds two keys, so I'll show that, there's two switches, two neopixels and you can, you know, that's just connected directly to like two GPIO pins for the switches and then one GPIO pin for the neopixels, it's really simple, there's no like GPIO expander or assistant or whatever, it's just like literally two switches, but you can, you can cut these traces and then rewire them however you like, it's kind of fun. So that's that and then this switch goes here and I'll show you what it looks like. So I just wired this up so this switch is basically mimicking this one, it's on the same GPIO, so there you go and then, there's no, uh-oh, uh-oh, I think I uploaded the wrong code to it, oh no it's on set by one, sorry about that, okay, now we're talking. Okay, so this switch, I have like, you know, it's connected to same GPIOs, this one, so you can see the neopixel shining through, it's really bright, but it's shining up and it's, you know, way washed out on the overhead, um, but here, you know, it's kind of illuminating the bottom half of the key, I will say it's not an even, um, illumination, I kind of wish it was, but I think that's just like part of the, part of the bargain. Did I mess this all up? Hold on, let me reset this, just in case, no, weird, I don't know, maybe I uploaded the wrong example code or something, but um, anyway, we've got two switches and normally each one lights up, but I don't know, maybe that must stop working, um, but it still shows like you get two keys and the LED's coming through, so all I have to do is on, um, these I'm gonna just swap this neopixels again, fix the reverse-ness of them, um, and, uh, I also added a Stem AQT connector on one end, there's a little spot here and JP was like, hey, can you put a Stem AQT on there? I was like, yeah, that's a good idea, so I did that, so those, those got ordered as well. Alright. Okay, that was so weird, what did I do on here? Oh well, we'll never find out, tragic, um, okay, but usually doesn't work, great, so that's demo number two. Then the third thing I got is, um, it's Stem A Sunday, I put together, um, this TCA4307, so this is an interesting, it's a hot swap I2C controller, so it's perfect for Stem AQT because you put your I2C controller here in the peripheral on this side and what it does is it doesn't connect them until like they're both synchronized up and, um, there's no like jitter, like sometimes if you hot plug, the, the charging of the SCL line on the peripheral will, will, will cause it to kind of stay low for a bit, which means all of your I2C gets desynchronized because your clocks have to be like whatever nine, these are nine clocks per transaction or whatever number of clocks, and if you're off by one like everything gets kind of like messed up, um, this is why normally I don't recommend hot swapping I2C, or if you do just realize that there's a risk that you're, you're, when you hot, you know, you connect a cold device into an active I2C controller, the peripheral will, will cause it to, to hang, so I was gonna show a demo, this I definitely don't know if it's gonna work because the thing is, is that, you know, once you have the controller running and the peripheral charged, it doesn't do the hanging thing anymore, but let's try it. So I've got my I2C scanner going on here, you can see it's, it's testing each one, so let me see if I can make this hang. No, see, this is the thing, it's not gonna hang because I'm doing a live demo one more time, otherwise you're just gonna believe me that like, you know, it broke like 15 times when I was, when I wanted to break, it doesn't break. Let me see. Huh? Well, it's supposed to hang. Usually when I'm not on camera, if I plug it in, it actually like, faults, it stops because the I2C gets into a bad loop because it's the, the SCL line got triggered. The problem is that once you've plugged in a peripheral, which I like, you know, plugged in a bunch of these earlier, once you plug it in it charges up the capacitor on the SCL line on the peripheral and so you don't, you're not gonna get that hang effect. Oh, there you go. Ha, I knew it. So you see, it stopped. It hung because I finally found one that was like truly cold, so the capacitor was, you know, completely zeroed out and then that charging caused a glitch and so the scanner actually stopped, which it shouldn't have, right? It should have just said like, that address 45 wasn't found or, or it was, maybe this is, that's the address this is on 44. Maybe if you just plug it in exactly the wrong time while it's, well, trying to get a response so you can get the I2C controller to crash. So the neat thing about the TCA 47, 4307 is that it doesn't ever happen when you have it plugged in because it, it doesn't connect both sides of the bus until both sides are prepared and you're not like in the middle of a transaction and then it will join them together for you. So like people who've done this know exactly what I'm talking about. If you haven't, like just hot swap I2C devices and eventually you'll cause this crash. You'll be like, why is it crashing? That's why. And this is the chip you could use to fix it. Oh, there you go. That's a, my demo. I'm glad I finally got it to not work. That's how demos go. The ones that are not supposed to work work and this ones that are supposed to work don't. That's engineering. Okay. And then finally, before we head into the great search, we do have a super secret. It's not out yet. Yeah, this is a world premiere. World premiere. We're showing something that no one's ever seen before. What's going on? Don't tell anyone. Yes, actually tell everybody. So this is under a bar go, but we got, we got permission to talk about it. So Digikey has a new service that they're adding. It's called the part tracing for cut tape. And so let's go to the overhead and I'll show what it is. So chances are you're used to getting, you know, this is some cut tape 0402s or something or maybe 0201s. And you're like, yeah, like I know these. This is, this is cut tape, cut tape, get your parts, peel them off. But what you don't have is on the back of the cut tape printing. So let me get like real down here. Okay, that's pretty, pretty good, right? Okay, you can see it. So on the back, you can have custom printing. Maybe make that level. Oh, yeah. Yeah. And then let it focus. This is it's curved. Yeah. No, okay. Now you're good. Super crisp. Okay. So you can put date codes, lock codes, country of origin, manufacturer, sales order number, purchase order number, and your own component ID. So, you know, you can say, you know, if this is your component ID or is this your number 111, you can say how many there were, you can say what it is. Okay. So like, you know that you have like 0201s, you are never going to know what it is. Like if you, if you lose the bag that came in, there's no markings. Even like 0603s sometimes don't have markings. You know, sometimes actually 0805s, I've had 0805s that don't have markings, depending on who you're getting the phone from. And then capacitors, yeah, you definitely had a lock. So it's neat about this is that on the tape itself, it'll tell you what it is. Great for if you're doing outsource manufacturing or even if you're just doing like your own in-house manufacturing and you get these blasted 0201s where you're like, you know, it's like dust. It actually looks like a mistake. It's like, oh no, they forgot the resistors. No, they're there. They're just really small. So I got sent two examples of it. And so we'll try this out too. And then for those who are interested, let's go to the computer and I'll show you where you can find info. That's secret. Go to digikey.com slash end slash resources slash part tracing part that that's tracing is the I can't make this part big. But that you can add tracing ID. Here's the stuff you can add. And there's some information you have to looks like they're printing on all eligible cut tape automatically. So it doesn't doesn't look like it's no, it's free. Wow, cool. All right, even better. So pre service, it comes automatically. I guess you don't have to opt in but not all parts we're going to have this to start. So it's definitely going to take it's going to be for like fiber paper backed cut tape to start because those are the easy to print on like if you have those big plastic ones, those are you know, not going to have it because it's harder to print on them. But you know, maybe they can start with all the 201s or 402s capacitors and inductors like the toughest ones. And then eventually they can maybe move up. So this is a this is kind of neat, you know, like maybe the machine that normally does the counting and cutting will also do the printing. So it's a kind of neat thing. They said we're working on this for like over a year and a half. So it's finally launching and I guess it'll be public on Monday. I ordered some cut tape. So I don't know, maybe we'll see if the cut tape order comes with some printing on the back Monday's in a few hours, we'll see. Okay, let's see worldwide premiere. Let's see eight millimeter paper carrier tape with at least eight inches. So you have to do the math. But check out more info. To be honest, I did not. I just got these like on Friday. And I was like, gonna check this out. So this is all new to me. But this is really neat. I think I will definitely use this because I have those little tweezers. And like I have to, you know, I want to have cut tape, I have to check the values. It'd be much nicer if I actually just had the values printed on the back. And I think most people who deal with small parts will agree. So okay, check that out. Okay. All right, next up, we have our great search that we're going to do this week. Yes, it's a didgy key double header. It is. So we have the great search. Did you key logo on the back? They printed a logo. Why don't you show that? It's so cute. Hold on. I didn't see that because it was at the very end. Look at that. They're small. Wait, it's upside down. This is like a didgy key logo for fans. Yeah. Okay, anyways, sorry, back to the great search. You're talking about. Yes. All right, the great search brought to you by didgy key and eight for every single week. Lady Eda, what is the great search this week? Okay, this week's great search is due to a part discontinuation. I have to find a replacement for our resistive touchscreen controllers. So we have lots of screens if it's kind of known for all the TFT screens that we stock. And when we have ones with resistive touchscreens, we'd like to put a resistive touchscreen controller driver on the back. Some chips have, you know, multiple analog digital converters, you can kind of do the resistive touchscreen handling on chip. But you know, a resistive driver is not too expensive. And for boards like the Raspberry Pi, we can connect a touchscreen to Raspberry Pi, we add an I squared C or SPI converter to read those analog values of the resistive touchscreen and convert them to like X, Y coordinates. So for many, many, many years, we have used the STMPE series, we started with the STMPE 610. And then we updated it to the STMPE 811. And we were using that for many years. And then it got discontinued, we were still able to purchase a bunch of parts. But as of this week, like we cannot get any more parts like they're really gone, we went through like every back stock every book or everything. So the STMPE 811 is no more. So we have to find a replacement. And looking for a replacement, one thing I really liked about the STMPE series is it was both I squared C and SPI. So it would be cool if I could find one of those. That said, if not, I'm willing to go with, you know, one part for I squared C one part for SPI. I'm looking for something easy to use. And most importantly, I'm looking for something that already has Linux kernel drivers, because I don't want to have to write a driver for the resistive touch screen. I really like it if it just like magically worked when I connected up the chip and gave it a device tree overlay. So let's go to digiki. And let's first up, let's show the part that is sadly no more. It happens, you know, you have to be ready for it. That's why you buy stuff, you know, if you need product to the last 10 years, you have to buy 10 years worth of stock, or you have to just be ready and willing to re engineer it. Don't ever count on a part being forever, even from large companies, they eventually stop. So this is the STMPE 811. So sad, a four wire resistive controller. It had this really nice thing. It was both I squared C and SPI. So just for fun, let's see if there's any that are I squared C and SPI within the touchscreen category. I don't care who it's by. I don't really care what package it is. Obviously, I'm not going to pick obsolete. I want to be active. voltage supply doesn't matter because it's going to be different. But as long as it covers 3.3. Oh, I do want surface mount and the package doesn't matter. I'm not expecting to get something that's the same package. It's that's a lot to ask because there's not that many resistive touchscreen controllers. So there is there's a couple. So there's the while this one's not active. So let's let's only look at active ones. So it looks like there's this BU 2121 nice symmetric name. This one looks pretty good, but it's in like a BGA format. I really, really don't want to deal with. So unfortunately, that one and I say no. So let's look at the BU 2124. So it's not, you know, too bad. The pricing is a little expensive. It's $2 for 1000. Considering usually I can get a touchscreen controller for under a buck. This is where it's like, you know, how much do I want a chip that does both versus the price? In this case, I tend not to need both I squared C and SPI at the same time. Again, for Raspberry Pi displays, I'm using SPI or I use one or the other and I'm not I'm not switching between the two. Same with shields and stuff. I have a touchscreen shield. I'm using only one or the other. I don't switch between the two. So Jordan, how do I know if there's a Linux kernel driver? Well, I actually opened up if you go to github.com and then go to Torvalds, Linux, Blob, Master, whatever input touchscreen. This tells you all of the available touchscreen drivers. Are they any good? That's for me to find out later, but I can at least find out if there is some support in the Linux kernel for them. So in this case, I'm going to search for this part number and see if anything comes up. Unfortunately, nothing has come up. So I start deleting some characters. So it looks like the 21029 is supported. This is the 21024. So it might work. But you know, it's not it's not guaranteed. And let's see. There's the Oh, here it is, the 21024. Okay, so this one is supported. So that's cool. So this is a this is an option for me to look at. Just just nice and positive. Again, you have to be careful about your search because it was the is a dash 24. So you just delete characters off of the end when you do the search until you find one that's close. And then sometimes it also supports the variance. So yeah, that's what you got the 2102324. So it's cool. So this is supported prices a little bit high. But I know that it's available. It's also only eight bit, which I feel like I could get more bits for two bucks. But maybe, you know, they're just like, Hey, you know, if you're desperate for something that does I squirt CSP, this is the only option you got that's not BGA and it still exists. Alright, so let's go back and keep looking. So let's get rid of interface. And let's so we still have active only. And I remember I really, I really don't want to do with BGA. It's always, I mean, I'm not against it. But like, let's not write. It's my preference. So let's, let's look through all these packages and remove ones that I don't want. So DFN is okay. I don't want BGA or chip scale, or WL scp, which is also chip scale. QFNs are okay. QSOPs are okay. Sops are okay. I don't want CSP again, chip scale, I don't want QFN, QFN, that's okay. More QFN, SOP, QFN, no BGA, QFN, TSOPs. I'll go up to 32 QTSOP, but 64 QFP is ridiculous. I'm not going to take that. That's too big. Alright, so I got rid of the BGA. So at least I'm not going to get any parts that I'm totally unwilling to use. And let's look at normally stocking. So I'm only looking at ones that are that are around. So to start, I'm actually going to look at, so I'll tell you something just to watch out for. So normally I would search for like interface, but I noticed that there's like I2S here, and then some say serial, but when they say serial, they mean SPI. So I think I'm going to like, I will acknowledge that there's this interface selector box, but I don't completely want to use it because I'm not sure what serial means in this case. It's kind of obscure. Is it UR? Is it SPI? You know, who knows? Like why is it I2S in there? So don't leave that be. Next up, I'm going to, so there's nothing really else. All of these are within the voltage ranges I can use. I don't really care about the current supply or the operating temperature. Again, the packages are okay. Voltage reference, you know, I'll deal with it. I kind of don't want to, but I'm not willing yet to say no tubes. So instead, I'm going to just do my classic search by price. And I see immediately, like there's some super cheap ones up here. And I kind of like, oh, I've got the Rochester. Let me exclude the marketplace once. So I look at only because the marketplace are gonna get the same thing, but sold under different names. So removing that, I'm only getting lots of TI parts. Looks like TI, SEMTEC, and my devices do a couple. But you know, the prices start getting really high. Again, it's like, you know, $4 per. Let me look at prices at 1000. So I can, I can honestly compare these. So yeah, basically, you know, there's all the parts that are like under $1 is going to be TI. And then SEMTEC comes in a little bit. All these are 12 bits. That's kind of good. And then it looks like, for my options, these are kind of different packages in the same part. See, it's like TSC 2046 and then IPWR. That's this TSOP and then IPW. This is the non real. And this is the QFN version. But it looks like the what's definitely popular here is this TSC 2046. It's very promising. Because again, I don't, I want something that is inexpensive, reliable, and will be around for a long time, right? I want all three. So let's go here and let's search for TSC 2046. So it looks like the TSC 2046 is actually supported under the ADS 7846 driver, which is a which is a driver even I've heard of. So that's a popular touchscreen controller. And it sounds like this is like the next generation. And it's registered compatible. So you can use the same driver, which is nice. I like that. So this chip is going to be really good. And this one is SPI. And then down here you see I squared C serial. This one is the TSC 20 2007. So this one is also supported. And it looks like there's a couple different options. Looks like you can do ADC can act. It can act as an IO expander or something. Not weird. So these are two good options. Both are available in 16 TSOP. Kind of wondering if these are pin compatible. That'd be kind of neat. Let's see. Let's see, sounds like there's there's a couple families. This is the there is a BJ version. There's a QFN version. Is there a TSOP version? Oh, weird. Huh. Okay. Maybe it's not actually available in TSOP. So it's available in QFN. So let's look at QFN here. And then let's pop back over here and download the TSC. Sorry. Sorry. I downloaded the wrong one. Okay, so this is the TSC 207. This is the I squared C one, which has two address pins. Okay, sorry. This is the TSOP. And then let's download the 2046. Looks like this is from Burr Brown, which they got acquired a bit ago. Okay, so look VCC x plus x minus y, BDD and then ground and CNC ground VBAT ox. So the this has like some more options. Ox D clock. Okay, so it looks like it's a little bit compatible. They're not completely the IRQ change. So they're not pin compatible. But there's the same physical size. So, you know, whatever, that's good for me. So these are the two options. And then, you know, I actually went over to the TI website to check. Were there any touchscreen controllers that had both I squared C and SPI? And the answer is no, there aren't. So I mean, I kind of wanted that couldn't get it. But I am really happy that I can get two touchscreens that are kind of from the same family. So hopefully they can share some of that driver code. One I squared C one SPI, same package. So, you know, I might be able to like, at least we use the footprint somewhat, you know, it's like the copper traces would be different. But the footprint of the part would be pretty similar. Left hand side is the same, right hand side would need to be rerouted. But that way I can maybe make breakouts for the same chip that would be I squared C or SPI and it would allow people to use resistive touch controllers with Linux and then hopefully Arduino, there's probably drivers already existing and then we'll write something in Python as well. So that's kind of going to be my choice for replacing the STMPE 811 is going to be this TSC 2046. Sounds cool. It's also like I think the the name of the next Blade Runner movie. Alright. That's a great search. That's it. Alright, two questions. Did you have a part number linked to the key switch holder? The socket, they're called kale switches. Okay, we'll have them in stock. They're not available from like your common distributors. However, there's a lot of like DIY mechanical keyboard sites and they're available there. Okay, some folks answered this, but they want to know what's the barcode on the cut tape on the cut tape. And someone said the first alpha numeric code is represented in the barcode that code traces a piece of cut tape back to the original real it came from. That's cool. Thanks, I didn't know it. Yeah, but that doesn't make sense. I mean, usually if you're doing, you know, you want to track parts, we use barcodes to track our parts too. Yeah. Alright. People like to part development in real time here. Yeah. And maybe for a future one USB hub controller. Oh, I yeah, I'm making a breakout for one. And I'm going to try it out. And then if it's good, I'll do it in the great search. Good. That's a good suggestion. And there's some good USB hub chipsets that are available. Someone says Genesis logic, or sorry, genius logic is good. Okay. SMSC hubs are popular. Okay. Good. No. Yeah, yeah. SMSC. Those are the microchip microchip purchase them. All right. We'll see everybody during the week keeps staying safe. Tunnel light in it. We'll see everybody on ask an engineer this week show and tell. And Pedro doing we got JP doing the product showcase on Tuesday workshop on Thursday, Scott doing deep dive on Friday. Yeah. And a whole bunch of videos and more all throughout the week. Thanks for supporting us. If you have time, you have an hour and a half. Go to our website, you'll see the banner. And there is yes till the end of today, you have a little bit more than an hour. All right. And then we're gonna shut off the code. See everybody soon. Thanks, everybody.