 Okay, so we're trying that again Yeah, that's a technical check to make sure people are paying attention. Yeah, luckily I had a caligraphic Okay Okay Hey, Deskers and Yeah, we're back. Thank you last week we had some family stuff we're doing and now we are Back to our desks. Oh, which is great. I miss my desk. Um, it's also good to see folks as well This week was exciting. So you actually kicked off this week. You went to an event. Yeah So let me just quickly talk about some stuff logistics. We have our full suite of shows this week from JT's project pick of the week 3d hangouts with Noah Pedro show and tell Ask an engineer JP's workshop Deep dive and then all the videos throughout the week and more Over the weekend. I went to hope it's st. John's University. Congratulations 2600 and the Hope conference. It was fantastic special thanks to st. John's University for hosting an Amazing event. I'm gonna post up more stuff, but just to give you a taste. Wow. They still have the poster Yes, just give you a taste of what's happening there. I think this is the first time Well, this isn't the first time that people took photos of the 2600 van. This is 1981 Dodge Ram before I think they like became Bell well, no, like yeah before dodge came something else, but I think it's the first time that someone has 3d scanned The van you scan the van I scan the van. I am the man down by the river who scans vans Okay, so you're gonna you're gonna be able to 3d print a little And so not only will you be able to 3d print it? But I think I'm gonna put it in video games and so you can drive to 2600 van and like hack video games. That's fine Cool with the free Kevin sticker and everything. Yeah Oh Designed the free Kevin sticker. I had a lot to do with the free Kevin movement Yeah, if you go to the documentary freedom downtime, you could see like a 19 year old me leading a protest outside Muramak Studios so we did that and so more ahead but Super fun event really good to see a lot of people in person It was Wholesome and heartwarming. Oh, so Lady. What are you doing this week? Okay? So, you know this week I'm from well first off I tried to catch up on email because we had some had so many visitors, which is wonderful You know, we had a lot of people who weren't able to visit the last two years Family members and such and so was it was really great to see people But catching up a little bit so one of the things that I Wanted to Revisit and like I know I have like 8,000 unfinished projects, but why not add another one? Which is I'm thinking of D zombifying this old project called blue for easy key and easy link these were really cool Bluetooth classic boards that we designed Like 70 years ago. We worked with the Qing who was an IE student at the time I think we're just graduated from ITP and actually wrote the initial firmware, you know, and we We actually gotten if I think if you wrote the firmware with like a kind of like part of copy and CSR The Val, you know IDE and then we actually went and got a license to use CSR and the CSR chipset Which is what is used in like? You know, well at the time was using like 80% of serial Bluetooth serial and HID boards now. There's actually a lot of other chips, but So the the cool thing was we did get it working the problem is that using CSR Really really really really was unpleasant. Let's just show the boards often people where they want to go to my computer real fast so So there were a couple of them and you know, they're just continued now But there was one that was you know, so we had to get these modules that had the CSR chipset and we got them FCC certified we get a mirror certified and like we had to get ones with tins and We programmed the boards which used like this really terrible like shark programmer thing that was like, you know, 300 bucks It did we didn't get it working. It worked worked pretty well. So the easy link was a transparent SPP protocol Bluetooth classic board What's interesting is is Bluetooth classic had like seven profiles and they were like Set in stone like you could have it be audio or you could have it be a serial link Or you could have it be HID, but like really like there was it was very limited It was like the classic Bluetooth and really like clearly tried to fix some of these problems by having customizable Profiles and like, you know, what? Endpoints that are for like the Bluetooth connection like how do you get how do you read and write data from different? Elements whereas SPP really was your like it really really was just you are Bluetooth because at the time like I don't even think USB was that popular yet when Bluetooth classic was first invented and so they were like We just want to replace the RS 232 link, you know, so, you know, SPP was how they did it And SPP had, you know, one cool thing about it is it really, you know in Windows or in Mac and Linux It showed up as a COM port like it looked transparently like a serial port And so this easy link was basically like a FTDI cable but without wires like, you know, you would when you paired it to your computer Your Windows Mac or Linux computer would show up as a serial port of a COM port and then you could send data back and forth and we also got the DTR and RTS and CTS pins working so it's got the control flow and the reason that was cool is that when you had control flow You could actually program like wirelessly And Arduino or an ESP32 board is kind of cool to be honest It, you know worked and then you could you know, you basically acted like a FT232 or CP210 and board so The easy link was very neat, you know that the real secret was that we got the The control lines working You know basically flawlessly through the OS, the OS thought it was setting the DTR pin and the DTR pin would get set And then there was the easy key which was Same module but programmed slightly differently and this would act as a Bluetooth keyboard and it was It's interesting is BLE has keyboard support. BLE does not have SPP support. You definitely use classic BLE does have HID support, but really like 99% of things want to use Bluetooth classic for keyboard and so It's a Bluetooth classic and it's like the buttons were just like, you know immediate key presses and so it was just like You know transparent keyboard You know generation device who people would you know You could put this on a joystick and connect each button to the GPIO down here And it would just like magically show up as a keyboard and it would press keys You could set with the key map you wanted and it was just like cool and awesome and everything So the problem is is that You know we love this product and we were selling quite a few of them and then the company that made the modules like went out of business Or like something weird happened And then like we couldn't find another place and we did and they were like we'll make them for you And then like we paid them and then send them and then like it was just it was just like it was kind of a nightmare and like CSR Like absolutely like so we tricked CSR into giving us a license Um, and I did it. Um, I don't think this is I mean it's been like eight years I think you can see what I did special limitations are over. Yeah. Well, I mean like CSR I don't know if they exist anymore. I think they were like purchase purchase purchase I think they're like broadcom or vago now, but Um, they would not answer my phone calls to or emails to get a license and you need a license It was like a $5,000 license To use their IDE and get permission, you know to use um the IDE and SDK to program the CSR chips And so what I did was I went I went to digikeys. This is digikeys help me out here Um, I went to digikeys and I bought like they had a starter eval board kit And it was $5,000 and part of the deal was like buy the eval board kit you get two boards a programmer and You know the license like it's a bundle deal, right? So I was like I I bought the bundle deal which was like a physical thing from digikey And then um, they sent it to me and so then like I tried to activate the license and CSR Was like who are you and like we don't want you You're weird. You're not a big company and I actually had um my digikeys sales rep Um yell at CSR and say we sold this to them. You have to give them the license key Um, this was like in 2014. So that's how I got the license key for CSR Uh, and I think I think like the day after that happened They like turned off that capability of like getting around their System uh, because again, they really did not want individuals to have access to the CSR SDK You know, honestly, you can download it pirate it on the internet. I'm sure Um, but because I was selling a product, I wanted to like do it right, you know, so I did it right Anyways, I couldn't get the CSR chipset anymore And I just like I was just like I had such a headache from this product and like, you know I still have like thousands of modules that I can't use like they're not programmed right and like they don't work and it's like I just kind of was like, I hate this and I want I was like, I'm going to use BLE. I'm going to move to the nrf chipset, which was joyous to use in comparison Um, but you know, I still did really like these these products and there are still a lot of Uh boards and chips that are programmed over you are and so having this with like I was like I want to bring this back and so as I was you know, I kind of forgot about this board but then I was I was working on the um esp 32 v2 feather Um, you know, one of the things that I thought of was um, you know, this little module can do bluetooth classic with esp 32 and it's impressive. It's like Way, way, way more fun to work with than CSR and it's like the you know, they probably have code for SPP and h&d even if it's not nonduino. It's at least in the esp idf So I'm I you know, like I'm doing like a meeting or something. I was like, oh, I'm just going to redesign the easy key An easy link. It's sort of the easy link to use the pico module and it's it's the same width, which is really nice It's actually a little bit narrower. No, sorry. It's about the same width, but it's a little shorter So you have to make the border even a little bit tinier and um, you know, what's nice is You know, I can put like a neopixel on it so we can the micro neopixel here for status instead of just an led because I'm like not dealing with this nightmare ide sdk that you know I can't actually like really code anything and it like It worked great, but it was like, you know, you can only do what it does and you couldn't really do anything else. So um, you know, well, we're gonna get like you know the uart output and uh, it's like level shifting and a pairing button um So this is kind of, you know, you can use any pin But it's sort of my idea of like maybe like resuscitating this project, which I would like to do Uh, because people I think really liked it. So um, will it work? I don't know, but I thought I was in I was in a heat stroke From you know haze from this week's 90 plus degree weather So I did that so, you know, we'll we'll order those PCBs in the next couple weeks and we'll see how that goes And one nice thing also about this is um, you know, there's the module that has external antenna So people if they want if you want to program a board that's like 500 feet away Just get like a big ass 2.4 gigahertz antenna And you'll be able to do, you know Bailey bluetooth classic from a far distance. So, um, we'll see how that goes. I will work. I don't know. I'm working on it Next up Ding ding ding. What's that sound fill? You mean more cowbell? It's time for cowbell. Yeah, so a little bit of uh A little bit of history with this so one of the things that we needed to do was Come up with a name for these pico w Shields or whatever and people were calling them peak house. And so I said, you know, what about cowbells and uh, yeah, I mean it was it was kind of spot on we had done a video where we did a Cricket project of a robot project and so we we did some iterations and eventually like we got a logo And we wanted to kind of go with like a dairy theme and like more cowbell, um and the the snl skip with christopher walken um, and uh, you know It just kept going and uh You just want to you wanted it. I'll see the cow. Yeah, so more cowbell. All right. So To your cowbells, uh, so I didn't you know, so you know, like basically, um I've just been like so busy that I never really made any pico add-ons Also because we had a feather we made an rp 2040 feather and so I was like well that way you can Take advantage of the ecosystem, but I think like this pico w The fact that they're making more boards in this form fact like one is like, okay interesting but two is Is a trend So the fact that there's two made me think like, oh, you know, I should like make some boards that work with the pico w Especially since like, you know the module I can't get a wi-fi module Plus rp 2040 for less than the cost of the board. It's just they're selling it like at cost And they're buying so many chips from broadcom that they can, you know, if they're selling the non W version for four bucks and they sell the version Um with w for two bucks. It's like I can't get You know wi-fi certified module for like less than that price anyways Um, so, you know, I thought that'd be interesting to like maybe make some add-on boards So, you know the one thing I started with is I always just start with the prototyping boards This is you know, the it's just fits exactly on the pico w or the pico and then You know every pin is broken out and there's some power lines These are the the power buses and then these are grounds They're the white markings with grounds and I added a little reset button a right angle reset button You could solder on because I like to have a reset button um Another be handy for people to be able to, you know reset it remotely if necessary, so this is um The first one the proto and then You know the thing I always do is I always make a tft version So part, you know part of the work I did was actually making the the board definitions for Making cowbells, which is like I have to make this Um object that has this dual smt connector and I really do like the dual smt connector We use it in the the feather tft So if you look at like the feather tft On the back I have this um These dual headers You know what they're they're two by n and they're connected through I just just connect them on the pcb And the reason I like this is that if you connect if you want to plug in a board like Here's you know one with the esp Plugged in you can see there's one row of pins down the edge that you can always connect to so like First off I think they're mechanically very stable the two by ends They're more stable in my opinion than like just the one row ones But and they're also a little flatter Um because they have pads on both sides But the second is that if you want to jump or to connect to it's like if there's free pins I want to make it so it's like you can easily connect to them if you wanted to so Having the headers on either side. So that was the first step was to just create This definition you can see on the on the back You know, uh, this is the outline and this is the usb and then there's these two pads And then the board, you know has the outline of here So it's good, you know, it's going to be bigger than just the pcb But you know, honestly, I think that's fine the pcb is a little skinny. So um So this one I'm starting with having like a tft And then maybe like four buttons and maybe I'll have a joystick and I'm just kind of messing around This isn't like anywhere near done Um, but then I wanted to add a sd card because a lot of times if I have a tft board I'm using spi peripheral I want to add sd because I can have images or like video or whatever like usually if you have an image If you have a tft you want some way to store Assets as well and and the the pico w and the pico Especially have very little disk space The pico w even less because you have to store the firmware for the wi-fi module And the firmware has to include the ssl stack and so you really have only a couple hundred k left So having an external, you know, these sd card slots are like, you know, a dollar But then you can add like gigabytes of space super easily for very cheaply as well Um, so the only thing was I was like, oh, okay, cool. You know, I'll I'll put on the back um, and then So I was on the back and I was like, yay, I'll just like stick it here and I was like, oh my god, this isn't gonna fit Um, it's just a little bit too narrow. And so what I need to do is I have to find um, a micro sd card That will hold on let me Measure I need something that's less than Like 12 millimeters basically and this one is um, like 13 or 13 and a half millimeters But that space between The headers I need I need that to um I need that to give me more space. Uh, sorry I need to have the sd card fit between that space because I want to use smt headers for Manufacturability easiness Um, and so it's worth it for me to find an alternative part That maybe we'll squeeze in here, which is what we're going to do for the great search Well before we pop off to that though, let's do some questions. Yeah Um, did the zero resistor on the sp32 s2 qt Pi antenna network provide a good enough signal not to need to be flushed out pi network I don't understand their question. You should push on the forms not to need to be flushed out Pi network. I don't know. Okay. I have to push on the forms. Maybe. Yeah, but maybe maybe antenna just a zero resistor Provided good enough signal to not need to be flushed out Okay, uh, this is comment, uh, thanks for preserving the pin out in the first six pins of the ads 1115 16 bit adc breakout board I was able to make pcbs that's compatible with the original stem versions. Yeah Next up, um, I guess for me the core thing about the add-ons any pico boards would be an external way to control power Approximant deep sleep as a pico isn't exactly a very power efficient chip in terms of deep sleep itself I know that's the first I've ever been using for their products that integrate pico I mean the the chip itself, you know does go into a sleep mode. It doesn't go into ultra deep sleep um You know that said it can go to under under a milliamp. I think You know the pico w does have an enable pin and so you could put an on off switch there um But you know, it's not I don't think the pico w or the pico was I don't know how much they were really Designed for ultra low power. I have to look at the schematic to see how they wire up the wi-fi and whether you can You can make it really low But the thing is is that you're not going to get as good as the esp 32 which can go into deep sleep At like 50 micro amps like that's definitely not possible with the rp20 40 I got a clarification for the other question and then uh, but let's first go to this question thoughts on adding a quick Connector to the esp 32 pico board You're working on example could add a neo key 1 by 4 board and do different tasks by button or marble the esp 32 um pico I don't I don't know what they're talking about the esp 32 pico board that you're working on I guess you're working on esp 32 pico board. This is the um, this is not esp 32. This is the rp20 40 and um We have a cutie pie or you know our feather and the cutie pie esp 32's have A cutie but a semi cutie connector on them. Yeah Okay, well, maybe I messed up that but I don't I don't know okay next up um The question before is is a zero-ohm resistor good enough not to need to tune the antenna on the cutie pie esp 32 s2 um the the the resistors that I I don't Know what they're referring to but on the esp 32 cutie pie. We don't use a zero-ohm resistor. Okay, I already put an rtc That would be great. So I guess real time clock I mean rtc does not necessarily mean it has a low power mode like you have to um, you have to be able to disable everything you want For I mean the rp20 40 simply does not sleep at less than about a half a milliamp Or point point two milliamps in the oh the easy key is the thing that they're referring to not the uh Um I I don't I mean I think I could add you know pins you could connect i-squared c But I don't know if I would make it a full Dev board at that point. So you should use a feather, you know the koto one on both and then uh, yeah to be clear The idea of having external power timer control for the pico is to be able to run With super low power mode like with the a blic chip you showed in api You would just we wire. I mean like the thing is is that nobody's going to pay four dollars extra for Accessory just because it does low power So you want to wire up something separately for those needs because it's like the the pico w I don't it's just the rp20 40s is not You're not going to get less than 50 microamps The way you do with the esp 32 cal bell would be the thing supplying power so you can just cut it off entirely You know what I also want a pony but I like maybe Maybe I'll make like a low power bell, but it's just like it's it I want to think Really express if something is not designed for low power. It's like Yeah, it's just it's just not like people who want to use bluetooth le With esp 32 they're like wow, it's not very low power. It's like it's just not designed for that I feel like I feel like when something's not designed for low power and when people Try to make it low power then everyone can play ins and say this really isn't low power It's it's very hard to take something that just is not designed for that and make it for that And I don't I look more carefully at the pico w, but if it's not designed for it It's really hard the mag tag we got to do low power with it It's amazing it lasts a month and that's the expectation if if we didn't do that If it only lasted a day people would say it's not really You know that's not low power. It's also is that what people even want? I mean like I will say that there's like, you know a couple dozen people who really care about low power stuff, but like Yeah, let's say You know most people are like keep posting keep posting some of the things that y'all do with it because that always helps us too Yeah, we'll take a look at everything but again. Yeah, the rp20 40s is not a low power chip. That's right great search Wait every single week ladies are powered of engineering to find things on digikey.com thanks, digikey Lady, you know, what is a great search this week? Okay, so this week I'm gonna get I'm gonna get to it. Uh, we're doing a Ultra slim micro sd card. So let's go to the computer so I can I can show this thing again Uh, so I want a micro sd card slot that is not wide like this But is because this is too wide to fit between these pads and it interferes I need something that's less than um 12 millimeters wide Um, so let's go to the overhead and I'll show how how wide these are to be wide Okay, so, um So this is uh 14 millimeters wide, which is like I said way too wide now You know ironically on on the pico w or the pico, you know, this would fit Because I'm not using these don't use smt headers use through-hole headers But on my accessories I want to use smt headers and so like the pads come out to the side Um, and so, you know, that won't fit and this like barely fits even here Uh, so one thing I did think I was like, oh, you know, I looked at um the teensy which I had one hanging round and um, this one actually is like almost exactly 12 millimeters, so I knew that this was possible to find something that would fit Uh perfectly in between um those pads I just need to use um Use my my didgerkie search capabilities So, um one thing to just note for is that this is not a push pull What like what you what you get when you get that extra width is there's the spring here and the spring is what lets you do the push push Um ability to you know, you push it in and then, you know, when you do this it like flies out and across the room um and then this is uh push and pull type so You know, there's trade-offs like that, you know, the Raspberry Pi computers also changed They were push push and then I think, you know, that was the the spring can break It's not really meant for, you know infinite insertion removals Um, this one, you know, it's it's not as like elegant because you have to yank it but It's skinnier and and you don't have the spring that can break. So let's go to my computer And uh, so we did Um actually cover the SD card holder in a previous great search Um, you can see it here like this is this part Um, I use it everywhere and it's it's wonderful and it's great, but again, it's it's a little bit too wide Um, so what I want to do is I want to find An alternative something that does very similar stuff and you can see this lovely rendering Uh, there's lots of these in stock, which is great, but I want something that's again a little skinnier Um, and one thing to note is that the the size is not documented It's not a search searchable element which happens sometimes especially for some connectors You don't get dimensions as a searchable thing. So what you have to do is just Look at them and then check the datasheet and just read each one until you find the one or You know, you do what I did you find a board that has the part and you're like, okay I know that this exists. I just need something that looks like that So let's look for a active micro sd um holder And let's view similar Um, so already we got a couple options. So this is the hinge type These are very slim, but I don't this is not a good board because I want people to be able to remove the card From the side that these hinge ones are really good when you have the sd card in the middle of your pcb So you want to be able to like flip it out, you know remove it and you don't have to have an edge Whereas the sd card i'm you know the card holders i'm looking at They need to be on the edge because you can you know, there's nothing in the way you can pull the card out So I do want to um remove Hanged lid so i'm going to select everything but hinged And then uh apply that to get rid of like the 12 that don't have it Um, okay, so now we've got a couple options. So You know the first one um first one we've got here is is you know what I've got already. It's got the spring This one I've actually seen this before I saw this on a They're ultra ultra tiny and like just like the ends go in it's like it's kind of weird One thing that is nice is it's high up above the board and so a lot of people use this um You can't put it in the middle of the board because often it'll float above any like resistors or maybe slim capacitors or even a chip and um Because it's not the the sd card doesn't go up against the pcb. It's actually kind of levitated The only thing that's weird about this is um, I don't like that the sd is like it's really exposed because only The contacts are connected So I've seen this board used as this connector. It is by far like the most compact You know simplest sd card holder, but um, there's no mechanical strength to it in my opinion um, so the next one is um We've got these amp phenol parts So this one has a spring. So I think we can't use this one This one looks like it's very similar to uh this, uh Lady, so let's look over here in the specs um, so this one Let's go down. We can see the Dimensional especially they don't they don't have dimensional specifications. Why would they add that? This must be an incomplete data sheet Okay, well, that's not very helpful Let's try This one Okay, this is much better. Um So I love it when the data sheets are scans of like documents So this one, uh, I think this is actually the same part that's on the teensy Um, because this is 11.95 millimeters. So it's like it's again very very narrow So this is like, you know the one I think I'm gonna go with Um, however, there's a couple other possible options Um, let's look at this one Maybe this one has yeah, this one has Also, this is um 11 You know 0.95 millimeters one thing I do like is it has a switch on it. Um, I like my sd card Most sd card slots these days do have a switch. It lets you know that Um, the card is inserted or removed. So before you perform any sd card communication, um, you can Check to make sure that the card is in place so you don't end up hanging on like waiting for data to respond Nothing, I don't think this really works But like if you are writing data to an sd card, you can kind of detect Right when it's about to be removed and like you might be able to flush the data really quickly Although I don't know how how fast you can do that before the contacts Um lose connection, but these are all really good options Uh, so let me just look for ones that are in stock And then let me look for Uh pricing, you know, we make sure the pricing at 5 000 pieces good. So yeah, these are cheaper For sure. Um, and you can see even the the thickness of the plastic at the bottom there that levitates it Um, and there's a couple options of these super skinny ones. This one's very cheap This one has that spring so it's going to be too wide Um, this is a flip top actually which just shouldn't have made it into this search But it did So the the one that is the least expensive. It's basically a dollar at the 5000 p spark is this Amphenol. So this is what i'm going to probably go with It looks like, you know, the the part on the teensy doesn't say amphenol So I think this is a generic Layout component probably amphenol first came out with it and then other people made Um variations that are very similar I'm going to try this I think uh, this is a pretty standard part So I should be able to get you know, I don't like to get connectors that are only available for one supplier So I'm going to first make sure that This pin out and pad Um, like the push pull sd card is available for multiple places And then I'll try it out But the good news is that you know once I lay out the pins Um, it'll work with all the code exactly the same because the contacts are exactly the same So this is my my great search Pink Oh gidoki, okay, all right. Let me see if there's any other things Yeah I think that Yeah, we did it. Okay. Okay. Good work lady. All right. Cool. Well, I'll think about the low power um cowbell stuff. I think it's I have to see how they set up the the power circuitry because I know that there is this um There's this buck converter and it's probably a pretty good buck converter um But yeah, it's like it's um it's it's interesting to see You know a lot of a lot of low cost debt boards are are designed for like they're optimized for one thing I feel like the pico w is really optimized for price um But I do know that there's an enable pin. So you might be able to like Use something to like turn off the enable pin and then you set like a timer And then it like brings it back up. But you know, you're going to I will say you're gonna have to end up paying A couple dollars for an rtc. And so then it's like I think people might be like Well, why don't I just use like an esp 32 instead which has the built-in Um low power capability. So I guess the question is like how much, you know, it's like it's it's a very delicate balance of um, you tack on Boards to add capability you're tack on chips to add capability You know at what point you are you like, well, I should just use like a chip that has all built in Just get a big honking usb power bank Or yeah, I mean like that's what I've always told people they're like, how do I you know? It's like I have like a hundred neopixels and like a servo And they're like, how do I estimate how long it takes them? Like well you power the battery and then you run your thing And then you count how long it lasts but they're like, well, can't I do math and I'm like You're changing how many leds are lit and when the power the motor is driven like every Second, there's no there's no constant current anymore. It's so spiky Do some rinse and repeat measurements. Yeah, like we did the we did the mag tag like I estimated it but really like we just Put it on our fridge and waited and then said like, okay, this is what it works out as because also batteries aren't linear Um, you know, you're you they self discharge The the current draw, you know, when you're in deep sleep mode is one thing But then when you wake up and you spike it like You're it's not linear, you know, you can estimate it, but it's not linear. So nothing really beats actual Testing and then if it's like, oh, I need to last twice as long. I always just say like it twice as big battery That's another thing like lipo batteries, honestly are like three dollars. You can get like a big one And that is the desk of lady to see y'all during the week. Thank you so much for spending time with us Good questions and more tonight. See you around. Okay. Bye everybody