 Welcome to the desk of Lady Aida. Hey everybody and welcome to my desk. It's me, Lady Aida. We're here at my desk for some late night hacking. Mr. Lady Aida is behind the microphone, behind this video deck, behind the computer. And simultaneously taking care of a baby at the same time. Yes, good work with that. That's right. Yeah, so we got some fun stuff at the desk today. I'm going to wrap up in about 20 minutes because we do have to give somebody a bath. Me? I smell like a horse. Yeah. Okay. I smell like milk. Okay. So at the desk, well this week we have been playing, well, we've been getting a bunch of stuff into the storage. It's good. We've also been playing with electronic toys that we've got around the house now that there's a baby. So let me show you what I'm talking about and what Lady Aida is talking about. So this is from Baby Einstein and it's one of the more popular kids toys for infants. And it just kind of does one thing. You just press the button at the stuff. But as we've seen in the comments on our videos about this, every parent is like, I would absolutely love to change the songs. I would like absolutely love to do other stuff with it. So we'll be placing four songs and it's like that's for a while. You're like, okay, I've kind of heard the song. Yeah. So check out the full video. We did a midnight teardown after we put our kiddo to sleep. This is going to be funny because like one day she'll look back at this, but like at night we hack her toys. So the idea behind this is we replace the circuit board. We make it so anyone can replace the circuit board. And then you can drag and drop any music files you want. We're going to do the cure prints, joy division, you know, what babies like. Yes. And so we're going to sing along with the baby and not get annoyed after a while because mental health of adults is also important. Yeah. The same song. If you're listening to the same song, it might not be a song you like, but they don't have licensed, you know, Depeche Mode. And you never will. Like that's the thing. And I think just how music licensing works and everything, you'll be able to put your own music on it. Now, the cool thing is the enclosure is identical. Everything's the same. We're actually going to have a mode that will reproduce the functionality exactly. We'll put the same songs on and everything. But then you want it to do other things on its own. So it could like, it could wake up at a certain time and say like, hey, you're, you know, 47 days old. It could do temperature. It could send it to, it could do some data logging, accelerometer stuff. There's a lot of fun things it can do, but it'll look identical on the outside. We're going to change the outside too, but this is just the first step. Yeah. So, yes, you did this whole tear down. So let's, we will go to the overhead. I'll, I mean, yeah, the whole tear down, but just by the way, a little side note, because I had to look this up. I'm like, how come, what's the intellectual property? How come they could call this baby Einstein with the trademark? Well, it turns out there's a licensing company for Einstein. Einstein is now one of the more wealthy dead celebrities up there with Elvis and Kurt Cobain. So they had to pay, or they made an agreement, this company that first did this with the Einstein group, the estate. And then I was like, well, how come Disney Plus has a show called like Young Einstein's or little Einstein's? Well, Disney bought this company and they probably had something contractually allowable that they can do. So these like, you know, because I'm like, well, what about the bagel place? Einstein brothers, I think is okay, because I think that that was their last name. But anyways, look up the Wikipedia page. I'm just like, that's neat. So anyways, I think something like 400 million in revenue. This company was clocking in for all of their toys and more before they got bought by Disney. And then they licensed it out to another company. So anyways, I thought that was neat. So we're going to go to the overhead. Yeah, I mean, it's interesting. So these are, you know, fairly well made toys. We want to think about baby toys as first off, they have to be very inexpensive. But on the other hand, they have to be very durable, right? Because kids love to like throw them in the, you know, floor and into like a pot of water or the bath or out the window or, you know, chew on them. So there's a certain durability, which I do like to the designs. They also have to last a long time. They have to, you know, usually last through many generations of kids, often they're, they're handed down for many years. So, you know, I took this apart and, you know, there's a couple of little just details of that, you know, make it very nice. Like there's hot glue that's used as strain relief on the wires and on this switch here that changes modes and turns it on and off. You know, it's a fairly nice switch. But also they use heat shrink because this is, you know, exactly where, you know, if it gets bent or shaken or vibrated, these solder joints are going to fail. It's, it's an epoxy blob, which is expected, you know, inside is some, you know, very low cost four bit ROM microcontroller, which is programmed, you know, once the factory is no flash, you can't program it. So people like, oh, can I just upload my own songs? No, you can. It's not like a, you know, it might be an 8051 underneath, but there's no flash memory that you can change. It's in ROM. What is nice is it's like a single-sided board, so it's pretty simple. And, you know, it screws in, so that's kind of nice. There's no glue here that you have to, like, you know, heat it up with one of those, like, I fix it kits. So we just have to replace this PCB with another design. And, you know, I'm probably just going to keep the, there's this elastomer pill button here. There's only one button. And when I tried to feel like we could, you know, the interface could support four buttons. We'd be like, now just do, just do one and, you know, we always do another version later. So we'll probably just have the same holes so that this piece can be recycled, right? So it's as close as possible. And then the, the speaker over here is a, you know, an 80, I think quarterwad. I kind of peeled this off a little bit. You can, you can sort of see, it might be hard to see what it's stamped on. It says 80 and quarter watt. So that's not uncommon. We actually stock basically the same speaker in the shop. We call it the thin plastic speaker. Very common in toys and gift cards and stuff. And so, you know, you get this, like, almost every toy store has this particular thing. It has two AA batteries. They're really low cost. And everyone in the chat has these. They're like, oh yeah, my kid's has these. So everyone has these. Everyone has these. It's like standard issue. And every, so I, you know, when I was doing Make Magazine and popular science and Hackaday and 2600 every person, especially tech person is like, I'm going to hack the baby toys. Well, you're too tired. You never do. So we're going to help you. Yeah. We're going to help you do this. It's actually a bit of work, right? Like once you get the, you know, the board, it's probably not too hard. So the question is, you know, what the, you know, the engineering is like, well, what do we want to put in there? And so there's kind of like two options. Either we could go with something like an RP2040, right, which is, you know, really fairly low cost. I mean, it's never going to be as low cost as whatever they made here. This is mass, mass manufactured. Like you can't beat somebody who's making, you know, literally millions of these a year for cost affordability. But the RP2040 and have flash memory, right? And maybe the songs are stored on the flash. And there's like an optional SD card slot if you want to toss an SD card in. And, you know, we would play wave files or very, we can actually play MP3s on the RP2040. It's a Cortex M0 plus, which usually, you know, it's not a very powerful processor, but, you know, maybe the dual core and the fact that, you know, we, I think we did 16 kilohertz MP3. So you can, you can do them. Just not really like amazing quality ones, but that's okay. The speaker isn't that great anyway. Well, this be the first baby toy that has like high quality audio or like supports agborbous eventually or something. Yeah. I think there's an agborbous decoder for microphone. I don't seem to use it. I was probably going to just use waves because Yeah, I'm going to use waves. Waves are like really, you know, they're easy to decode. They're easy to decode. It was good enough for me when I was a kid. It'll be good enough for my daughter. Yeah. Although MP3 is openly licensed now. You can use, you don't have to pay to embed MP3s. Yeah. I don't want Fraunhofer coming down here, shaking down my kick for milk money. No, shaking down the baby. The baby only has like two possessions in the pacifier and like a plastic ball. Yeah. So that's one option, RP2040. The only thing is, is that, you know, there's no SD, there's no, I'm like, sorry, there's no USB slot anywhere. I didn't want to do anything that required like cutting the plastic because it's like legal sharp bits. Plus everyone will freak out online. They'll be like, oh, you modded the case, your baby's going to choke and die. So what we want to do is the outside is going to be identical. Yeah. So then if you're going to use your RP2040 on one hand, it's low cost, it's really simple, but you'd have to open it every time you want to change the songs because there'd be like a micro USB. You have to change the battery once in a while anyways, but we don't want to do that. Yeah. At least not immediately. Yeah. You're going to have to change the batteries, but I kind of didn't want, like that is a different thing. Let's work one screw on the back and it's not too bad to open. Whereas this is, you know, a little bit more annoying. So then the second option is we go with something like ESP32, C3, or S2. Those are kind of my two options. And the reason is that those both have a round boot loader. You don't need a separate USB serial chip for them. And they both come in nice little FCC modules with antenna. And then you could upload the files with a Wi-Fi because we have in circuit Python and also honestly, have it to a file uploader setup. And then both can easily play waves or I don't think we have MP3 playback in circuit Python. So give us a reason that we should probably add it to be honest. I think there is an ESP32, there's an ESP32 MP3 decoder for the 10 silica and risk five, you know, maybe they do too. The C3 is tempting just because it's very low cost. But the issue is it never shows up as a disk drive. So, you know, you would have to use the Wi-Fi. I kind of like the S2, you know, it's not as cheap as the C3. But it does show up as a disk drive. So for people who are like, look, I don't want to have the Wi-Fi enabled because that's weird. And it uses more power. You would just, you would just use, you know, in disk mode, you open up. But for people who want to do like, okay, I want to drag files over, you could do that. And of course, it'll be SD card as well. So we kind of have to figure out, like, you know, even though it doesn't really matter what we choose, I kind of like to think through the process of, you know, what our design decisions we're going to make. Yeah. And check out our video, we're going to post these as a series. We just scanned in the PCB. That'll be the next thing. Yeah. So the next thing I got is, you know, Phil scanned in the PCB and take the PCB. I do a trace, you know, I basically, you know, you know, I rasterize it into monochrome. And then I simplify import into Eagle as like a background image, and then I trace the design. I've done this before. It's not, it's not too bad. You just trace the holes and the slots. And then, you know, now that I've got that, you know, I save it into my GitHub repo. We'll make a GitHub repo for all this, of course. And then, you know, I can start laying out components. So, you know, I think I'm going to have a couple different options, people to upload files, because I think, you know, I think if people are going to use this, and they're going to, you know, it's going to be parents, like, they're going to be really tired, they're not going to want to like, dig around with Wi-Fi. There needs to be a way for them to have the files upload over USB, over SD card, or Wi-Fi. I think that's, I mean, it doesn't cost that much to do all three to make the decision. To change the battery, you have to use a screwdriver anyways. And so we could also be slick and like, slip a little SD card reader thing through the battery compartment. But anyways, there'll be some neat stuff ahead. Yeah, no, I mean, to keep it from being, it's not waterproof, but it's slightly water resistant. There really isn't any slots. Yeah, you have to dremel through. And now you're dremeling. You're dremeling. I mean, you'd have to desolder already to remove this from the battery. Supply it also, you know, change the switch. So already it's like, that's a little bit as much like the idea that any parent with a screwdriver could just swap out the board. Yeah. And you're done. You don't have to do anything extra. So anyways, that's what we're working on. Yeah, okay. So that's my hack. Okay, cool. So we're going to move on to the great search. Oh, one thing. Do you want to go? No, I just want to mention one thing. So we just posted up the video for the floppy stuff. We got back on it after the holidays. I had to, you know, bring a child in the world. So the floppy feather wing tester and the floppy feather wing Ruben Capeville video is up. So anyways, check that out. But let's do the research. The great search brought to you by DigiKey and Ada Fruit. Thank you, DigiKey. Every single week, LadyAda user, power of engineer to help you guess you find things on digikey.com. LadyAda, what is the great search of this week? Okay, this week I'm replacing this toy. It's going to be overhead and I'll show the toy. We're using this PCB to have a different microcontroller. Yeah, by the way, that's the outside. That's the outside. And so I'm going to, you know, I know I'm going to use a microcontroller or something and all the microcontrollers I'm thinking of using basically none of them have DACs or they don't have DACs with DMA in them. And so instead of fighting an 8-bit DAC on ESP32, I was going to use I2S as an audio output because I wanted to have fairly good quality audio and I wanted to drive the speaker directly. And so, you know, historically I've used the Max 98357, which is a very, very popular and really wonderful I2S amplifier that it has, you know, only one little weird detail about if you change the clock rate, sometimes it does a little bit of a pop on Raspberry Pi Linux, but otherwise it's a very good I2S amplifier. And I wanted to, I was going to think of using that, but I thought maybe I would take a look and see if there's any other good options. So let's look at the computer. So this is, again, the chip that I tend to use. And it's extremely popular in DigiQ. You can see there's 50,000 in stock almost, you know, 43,000 here and then another 6,500 available at the factory. So, you know, this is a great I2S amplifier chip and one of the nice things about this in addition is it doesn't have an M clock input. So it's really good if you want to save one pin. But I also, you know, I've used this chip for, you know, like almost like a decade, it feels like. So I wanted to see if there's any other good options. Not saying that this is an option I'm going to go with, but it's always good to take a look at some other possibilities. So I'm going to look in audio amplifiers and I want to look at active surface mount sensors. And I'll tell you one thing that is interesting, which is, you know, you can search for this. The amplifiers that are, I'm going to say normally stocking and not look at marketplace just for now. One interesting thing is if you look at the amplifiers, for example, this IS-31, the first one, this one is a analog input one, not a digital input one. So in this topic, the analog, the audio amplifiers, there's mixed analog input and digital input. And so, you know, the challenge is is that you want to narrow down as much as you can, but then you will have to search through the data sheets to find some good options. That said, there's a couple of things you can do to simplify things. For example, you know, nothing that is 8 pins is going to be digital input. This is a microphone capsule input. Nothing with 8 pins is going to be digital, because if you're going to do I2S, you need M clock, B clock, LR clock, and data. So that's four. And then you need power and ground. And usually you have more than one power, more than one ground, and you need the two speaker outputs. And now this is 8, but that's like, that's assuming no other inputs. And if you have I2S digital, you almost always have I2C input, or you have a mute or a shutdown pin. Basically, you don't have 8 pins. It's very rare to have, I've never seen an 8 pin I2S input chip other than like the CES4434. And that's not a speaker driver. So what I decided to do to kind of simplify this is looking at, first off, I can filter on the power, so I have to drive this quarter watt 8 ohm amplifier. So the first thing I did is I just filtered out anything that was less than 300 milliwatts 8 ohms. And then no speaker amplifier really is going to be for the, the pricing I'm willing to spend, which is, you know, I'm not going to spend a couple more than a couple dollars is going to be more than 10 watts. So I can filter out and just look at that. Second, I don't want, I want either like one channel mono or stereo. I don't want just headphones. I mean, I don't mind if it has also headphone output, I guess. So that's fine. Although, you know, I think two channel stereo is going to always be more expensive. And then of course, you definitely are not going to fit that into an 8 pin chip. Next, you know, I can do power supply, but I think I'm going to leave that for last. Okay, and then there is package device. So like I said, I think that I'm not going to look at anything with eight pins. It needs to be nine pins or more. And I also, again, do not like BGAs in my process. It's, you know, very time consuming to debug them and to place them. And so I'm going to search only, and I don't want anything that's 48 pins. I'm going to go to 32 pins maximum. And then I kind of selected out all the BGAs. There's a lot of BGA amplifiers I found out while doing this. I also don't think I want 20 SOICs. It's going to be way too big. Get rid of these BGAs, get rid of this BGA. More BGA removal. 60 SOICs, you know, maybe that'll fit, that'll be fine. Okay, so let's, let's look at these. Also, our internet's much faster today, just kidding. Okay. So, and then for pricing, let's look at pricing for 500 pieces or more. And so there are features like I2S, I2C, and those definitely will be digital, but I'll say that there are some that didn't have I2S in the list that were I2S. So just something to watch out for. Another thing is voltage. I want something that will run off of I think 3.3 volts. So I'm going to narrow the search here. And then sometimes I don't have the power supply. So I'm going to move everything that needs 8 volts because I don't have 8 volts available. Okay. So now we've got a couple options. And I'll look at the mono ones later. But like I said, you know, these are mixed together. So this one, for example, is analog inputs. And then so are the PAM series, etc. Let's look at maybe mono instead of looking at the stereo. That's the only mono. Okay, let's see what we got. So down here, let's see, the max 98 is down here. Yeah, so the max 98 series is down here. Let me look at multiple. Let's show. Oh, by the way, I've never shown this. You can have, you can have a display like many more than just 25 at a time. So the max 98, 358, and 57 are down here. So, you know, this is ones that have a lot of stock in them. So I actually went through and like I kind of searched each one to see which ones were analog and digital and that just meant going through the data sheets. But it was worth it because I did find one that had that the pricing was a little bit less. It's, you know, about $1.50 in quantity, the TFA 9879. And this is actually a pretty nice amplifier that was available. So let's look at that. It has I2S input. So, you know, I immediately like honed in on like, okay, it's got, you know, an I2S input bus, PCM, you know, 3.3 volt logic. It runs from 2.5 to 5.5 volts. So it's great. You know, I'm going to have to have a little booster on my design because it runs off of two AA's. So I'll have to run it at 3.3 volts anyways. So this will be fine. It also needs a 1.8 volts digital supply, but that's fine. That's not for the amplifier. That's for the internal logic. And another kind of neat thing is that there is a I2C interface, which is a little bit more complicated. But it does mean that it has let's find it. It's got some cool I2C stuff that you can do. It's got a built-in like DSP with digital volume control, which I thought was really nice because oftentimes in your MP3 player, like it might be MP3 playback on your microcontroller, you don't have a volume control setting like that is a separate, you know, thing that usually is handled as a post processor. And most MP3 decoders just take whatever digital input and they just like kind of blast it out into the I2S data. And then, you know, sometimes you can do a multiply, but sometimes, you know, you may not have as much time to go through and multiply out every data sample before it gets shipped out. So having the DSP here on the MLog output means that like you could remotely or with a potentiometer that's not in the signal path use that to tweak the audio volume. And there's also an equalizer and bass and treble control. So I thought that was, you know, like zero crossing volume control, power limiter, basically a very nice, you know, I2C control interface for this very low cost amplifier that's also class D. So you're going to get good performance is good for like, I mean, what's funny is it says like good for portable gaming and MP3 players. So while, you know, I may still use the Max 98, 350, 375, I tend to use, and very interested in this part, I think it's a not often used. I've never seen this used in other people's designs, whereas the Max 98 I've seen a lot. But this is definitely my pick of the week for interesting chip. I'm probably going to make a breakout for this because I like that parametric controller, I squared C, I think that would be really useful when you can't do that on your micro controller when you're doing your audio playback. And that's a great search. All right, questions. We're going to do it and then we're going to bounce. Ready? First up, with a toy hack, is there enough room to put a small PR sensor under the part? The LEDs blink have a motion activated tune. I think I would add like a STEMQT port because there's a lot of space in the guts of the device and you would just plug in whatever sensor you wanted. Okay. How about C3, but only turn on Wi-Fi when you stick a magnet in a certain place with the thing inside that knows it through the case? Yeah, it's actually one of the things that Phil and I chat about is like, how do we, you know, make, maybe you make it so Wi-Fi isn't always turned on. Yeah. You know, magnet sensor or like a orientation sensor. Here's the good news. There's so many people, they just need a little bit of help getting this project started that we're going to see probably the biggest toy innovations ever. And the neat thing is everything is open source. And I think this is going to spawn a new industry of smart toys because there seems to be stagnation because it's always been a race to the bottom for price. But that's now possible for everything. Like you can get like basically Linux on a chip for, you know, and I think there is value if these things are like these toys are like six or seven bucks on Amazon. I think parents would pay $12 if it did everything and it saved them a lot of time and it didn't drive them crazy. Mix up. What is i2s anyways? i2s is a digital data format for audio. It's basically what all audio uses these days because it's less susceptible to noise and static. But it's a digital pathway, right? And it only turns into analog at the very end where, you know, for example, you have this amplifier speaker. So a lot of chips don't have analog outputs, but they do have digital ones. Next question. Aida toys question mark, a line of Aida fruit baby toys that are all open source hackable. Well, here's the thing, if that makes sense, we'll do it. Like we're told this is the cool thing about being an independent company that's supported by all of you. We're open source, no loans, no venture capital, no board. You know, we didn't blow our money on like the metaverse. So we can do things that are risky and interesting and innovative. And this might be one of them. I put this in the child mention it anyways. There's a lot of neat things with AI. I have opinions about AI. There's lots of great uses for it. There's lots of uses that can be further refined and defined. But one of the things that I want to do is AI teddy bear, kind of like a Teddy Ruxpin if you're familiar with that. But it would be a rule set that's like you're meant to talk to a child. What are the things that you want to say? And it's data sets that are wholesome and interesting for young people. Because I don't want kids just to like, Oh, I could talk to an Alexa or something like that. So anyways, does come it's in that's a little premium top secret. And I think that Oh, yeah, a different Macedon instance. Yeah, we're on Mastodon. Let me just post a link in there. We have the toots. We toot. He toots. We toot. What tootin go down? We toot. Whole lot tootin, whole lot tootin. Yeah. So yeah, one little side note to we've been on there since 2017. We were there before women's dream. We got ours on vinyl. We're like hipster Mastodon. Yeah. So. Okay, let's rock it because it's a lemon. We it's, it's a bath time. Yeah. The pair of customized sounds a drag drop to ST car. I think that'd be the most problem method. Yeah, I think so too. Okay, last one. This is really last one. If the mic controller gets faster and more RAM will be possible to run Linux. Yes. Yes. There are mic controls that can run Linux. Yeah. There's a there's there's more. There's more coming and more around every single day. Okay. That's our show for tonight. Thank you so much, everybody. It's now time for a bath. Bye bye. Bye bye.