 me JP. I'm a little loopy. Thanks for stopping by again. Have you been here all day? It's Circuit Python Day. We're all excited about it. Right there, 818 Day. Today, we think maybe fourth annual Circuit Python Day. We have had a huge day packed to the brim with live streaming. I'm not miming the whole show, Todd, but you know what? If you want to make funny remarks, do it over here in our Discord. Head to Adafruit.it slash Discord. Live broadcast chat channel. You can hang out there all day long because we're pretty much live streaming all day long. And we're also keeping an eye over on the YouTube chat. So stop on by. And what have we got? Let's see. We've had, here's what we've had. I've got my notes. Here's what we've had already today. We had the 3D Hangouts this morning with Liz Noah and Pedro. SynthIO panel. Paul Cutler led that. Thank you so much. Paul Fomey Guy did a game jam. Super cool. Maker Melissa was working on a Matrix Portal build. That thing looked awesome. What else? CPy Circuit Python Day chat with Jeff, Dan, and Catney. I'm doing this here now. Then we've got a deep dive with Scott afterwards. Then show and tell. And finally ask an engineer. So it has, it has been pretty, pretty swell so far. Pretty filled with great content. And I hope you enjoy sticking around and seeing some more of it. So what's this? This is my workshop show that's usually on Thursdays, but it got slid over to our Circuit Python Day today. Not much else has changed, I don't think, except for we have one unified coupon code all day. So if you want to go buy some great stuff in the Adafruit shop, then head on over there and type in sir. Oh, I have that wrong, don't I? It's CirquePy Day. Right? CirquePy Day. I hope I didn't lie earlier. Someone correct me if I'm wrong. I gotta, let me triple check my notes here. I think, I think that's it. Cirque, are you CirquePy Day? I think it is. Okay, yeah. So CirquePy Day should get you 10% off in the Adafruit store for the rest of the day. So you can, you can go and you can find some stuff, throw it in your cart. No hurry. But before midnight tonight, you will East Coast US time, you will want to go ahead and fire that off and use that coupon code to yourself a nice little discount. Let's see, what else is up? I've got MIDI Maniacs as every day should be CirquePython Day. So I've got my show on Tuesdays, which is the product pick of the week. And that is usually a little 15 minute long show, but I reduce it down into a little one minute excerpt that you can digest right here. So check it out. The PC joystick seesaw adapter with Stema QT, the connector coming off my joystick, my X and Y mapped to the PC joystick seesaw adapter with Stema QT, the connector coming off my joystick, my X and Y mapped to the position on screen of this little triangle that I'm drawing on this little OLED. If I press some of these different thumb buttons rather, I'm going to bring up some different shapes. If I pull the trigger, I'm just changing the screen to all white there. You can see some tearing from the refresh rate there. And then when I have one of these held, I'm mapping my throttle to the X position of that little pill shape, the Y position of that little box shape. And if I'm showing them both, you can see that happening. So we can do some cute little things here. This would be really great for driving a little pan tilt servo type of thing. The PC joystick seesaw adapter, I square C with Stema QT slash quick connectors. Let me try that one more time with the microphone on. I was just saying this is a great time and day to do a circuit python parsec. It being circuit python day. So check it out. There we are. So for the circuit python parsec today, I wanted to show you inside of circuit playground, the circuit playground library, which makes things even easier than just straight circuit python. In circuit playground, how to use the temperature sensor. We have a thermometer essentially built into the circuit playground, blue fruit and the circuit playground express boards. You can use them really easily. Don't get scared by all this code down here. That's a second, second example. But the first example right here, look at this. It's like nine lines of code. All I can, all I going to do is import the time library and the Adafruit circuit playground library as CP. Then in my main loop, I'm setting a variable called temp to be CP dot temperature. That's all you have to do to ask for the temperature. It gives it back in Celsius. Then I'm also converting that to Fahrenheit with temp times 1.8 plus 32. And then I'm printing those out. So you can see here, I'm getting it about 28 degrees Celsius, 83 degrees Fahrenheit in the workshop here. It's kind of warm. If I touch this with my finger, let's see if it'll get cooler or hotter or stay this hand, get a little warmer. Not too much though. My finger exterior of the human body temperature isn't crazy hot. I can breathe on it. Let's try that. What does that do? Spiked it up to 86. All right. I wish I'd brought an ice cube or something. I forgot it was going to be kind of warm in here. So for a second example, what I'll do is I'll go ahead and comment that out. Let's uncomment this and I'll set my range so that we can use the LEDs, the Neopix LEDs on the circuit playground, blue fruit as a type of temperature meter. So I'll go ahead and save that code. It's going to reload. And now it's going to light up LEDs mapped to how hot it is. So actually, let's change that range. Let's make it say from 26 to 32. So these are the minimum and maximum that I'm going to allow. And then it's going to map pixel brightness or pixel light across that. So if I put a finger on this, oh no, I can't really move the dial. I'll try breathing out again. Kind of got one more lit. Shut a thought of that. Sorry. So again, you can see here all I'm doing is importing time, the circuit playground library. And then I'm setting pixels, cp.pixels, makes it really easy to use. And then we have a little bit of a function here to do the scaling of the values. And then we're setting a peak as the scale range. And then we're printing out the temperature. We're printing out the peak. And then we are remapping for all 10 of those pixels. It's going to be either lit, this 50-50 here, sort of an aqua blue, or it's going to be off depending on where it lives inside of that range. And so that is how you can use the temperature sensor built right on board the circuit playground blue fruit or the circuit playground express using the circuit playground library inside of circuit python right here on circuit python day. And that is your circuit python parsec. Question from the chat SF Dave says, what development environment are you in? This is just sublime text is what I'm using. Nothing too fancy. I just have it doing some color coding. What do you call it? I'm forgetting the word now. But it knows that I'm using python so it sets the grammar properly for that. You can do little add-ons here. I'm using a little terminal. It's called terminus inside of sublime text. And you can see here, if I quit out of it, let's TQ. If it'll pay attention, it doesn't want to. There it goes. Almost. It doesn't want to quit right now. But it's essentially just a terminal shell and then I'm running TO, which is a terminal viewer via disco tool, which just makes it easier to find the circuit python boards that are plugged in. Syntax highlighting. Thank you, foamy guy. That is exactly the phrase I was looking for. The syntax highlighting in here. You can pick different color schemes and so on. Let's see. I'm trying to think. Do I have? Yeah, I don't have a good way to really move the dial much on that thermometer. That was a bummer. Maybe I'll gin up a new example of that one for the video. Yeah, I'm curious what other environments people use. There we go. So there's just the straight terminal. You can see where I am here. And then I'm using disco tool, which will tell me what circuit python devices or devices with a serial port that I can connect to are available and then I can pick one by name. In this case, the circuit playground blue fruit and now I'm connected just to that one there. So yeah, somebody says VS code has a terminal built in. Just press shift return. VS code with circuit pi sometimes with the serial monitor extension, Todd mentions. I use atom on my main workstation, but it stopped working on this one for some reason. So I switched over using sublime text here works pretty well. Alright, so let's see. What do we have next? You know, one thing I wanted to do is a little recap. Actually, I got kind of two recaps. So one of them is of the new guide here. And that is make that a little bigger there, widen that out. There we go. That is the ambient machine. Excuse me. That is the ambient machine, ambient sound machine that I've been building. And I just published the guide for this last night. So if you've been interested in this, following along the progress of this project and want to go build your own or use this as a leaping off point for another project, I know someone who saw it online and said, Oh, that's great, because I kind of want to just do a button box. This is a helpful guide, I think for getting started on any kind of just control control button box type of creation doesn't have to do sound. But if you want to do one that's going to play back audio samples, which is what this this does, this uses wave samples and the mixer audio mixer library in circuit Python in order to basically listen to or mute any of the sounds. And I also have a couple of volume positions. I'm sorry, I'm laughing because someone wrote the mop that's the IKEA box this is built into. Pen Pengu wrote mop it mop it mop it mop it in a cute square over on discord. I'll show you this. It's it's the I don't know it's it's the the breakout surprise star of the show is that word. So here I've got a link to the original. I always want to credit Yuri Suzuki brilliant instrument designer interactive sound designer general creative person who who created the original that this is a remake of so you can check that link out there. Go over the parts that are used here and some parts that you'll need to get such as our favorite IKEA box there the mop it with lots left over I have plenty of extra drawers and things to use, even though I've used one of the medium and one of the small drawers for the build. Then I've got some circuit diagrams in both the fritzing breadboard view and in the schematic view there so that you can see how things are wired up. This is using the Metro m seven. As Jeff was saying in the synth IO panel earlier today, the Metro m seven is a is a powerful, powerful board has a lot of speed a lot of processing cycles to work with. And it happens to handle this very well. Then we've got a little quick install quick start for circuit Python on the board there. There's the lovely Metro m seven that we're using. The code page here will take you through downloading the bundle and if you're not familiar with this by the way one of the many things that have been done over the last few years to make it easy to learn programming and with circuit Python and get your projects up and running quickly if you're using tutorials from the learn system are these project bundles. So when I commit my code to the GitHub repository for the learn system, I also commit the sound files in this case. So if there are assets that are used, those get committed. And the system automatically grabs the proper libraries. It looks at what libraries I'm using and it throws those into this bundle. So if you click this download project bundle, you'll get a zip file that is everything you need. So it's a it's a nice way to get all the stuff that has to get dragged over to the board when circuit Python, the correct version is up and running for your board. Put these files on and you're ready to ready to go. And here is the code for the ambient machine. And then I have an explainer here that tells you what all the libraries do and what the different sections of the code do from setting up your buttons to setting up I squared C for listening to the multiplexer. A pair of those I have in there setting up audio mixer. And then we're using an I to S amplifier out to a speaker built into the project. And then we get to fabrication and assembly. I have included if you click on this link here ambient box v one dot SVG. These are the scale CAD drawings that you need to either print out a template if you print it at one to one, you can use that to mark where you're going to drill holes to place all your switches. Same with where you need to drill holes on the back of it. Now, I used a laser cutter. So I'm able to do the drilling part very quickly and precisely. I'm also able to do a pattern on the back here that you wouldn't probably want to attempt without something CNC controlled. But you could. You could certainly drill a couple holes and use a small coping saw or something to create these rounded slots. But that is up to you. The only four that are super important are where you're going to screw in the speaker. So you can see we've got these these screws here connecting the speaker to the back of the small box. And then you'll want some holes in here to let some sound through. We're also using the enclosure as a sound board. So the back there is vibrating as well. And then I've also got in that template where you're going to cut and drill for the USB port on the back. In fact, let me got it sitting right over here. I'm talking about it and showing you pictures, but hold it up while I talk about it. So here you've got one of our panel mount USB C ports there. So you're going to drill. I used a Forstner bit, which is you can see it there in the picture actually. That's what I used to drill that hole there. I could have laser cut it, but I forgot. I forgot to include that in the file. So I just went went ahead and and drilled that out with a Forstner bit. Then we've got all of the parts how I've laid them out here on one of our swirly grids. So you can just use some little nylon 2.5 m 2.5 standoffs to connect that. All of the wiring is using our arcade quick connection. You didn't have to solder a wire to every single switch and to the multiplexers. I soldered on the multiplexer side of things, but those are little spade lug connectors that go on to the little lugs on the base of the of the switches there. So that made life a little easier and you can see I'm running rounds to to all of the switches there as well. There's some cable neatening that I'm doing in here. You'll also notice actually this is you can see it here in this drawing. Since these types of switches require a small hole to be drilled or laser cut right above the shaft hole in order to prevent twisting, that's a little removable collar and I didn't really want those holes there. It's also a little more painful to do that by hand. So I didn't include those, but that meant that my switches, if they got a little torque on them, they start to get all wonky. So I built these little jigs here, these little, I call them switch locks, but it's just some thin plywood, birch plywood that I'm using to slot over the body of the switches so they can't rotate. So that's a fairly painless way. You can also hot glue them down while they're straight, include the hole for the little registration notch any any way you want to or just live with them sometimes being a little wonky. Then I've got all of the I mentioned trying to try to neaten the wiring a bit here. This is it in its kind of sloppy state. Here it is after throwing some zip ties on some bundles of wire essentially and then laying it into the case. And by the way, those little locks for the switches, those are the same width as the interior of the small box. So it slots onto that pretty nicely, nice and snug. And then I encourage you to use either you could mask and paint this before you put your switches in or like I did, I just cut some cardstock, some yellow cardstock. So nowhere near as nice as the gorgeous yellow, I don't know if it's painted or acrylic or powder coated in the original, but it's an homage. And, and then you can go and play that. So that is our our new learn guide, my new learn guide for the week. And let's see, let me jump over to our chat and see if anyone's got any other questions. Let's see. SD Dave love the project bundles. Yes, they're fantastic. Absolutely. Any other things I can address? No. All right. Great. Some discussion going on there if you're interested about temperature monitoring on chips. Check that out in our discord. And then the other since it's circuit Python day, I thought I just talk a little bit about some of the many, many projects that circuit Python has enabled me to do. So let me go ahead and adjust this crop a little bit here, make this a little smaller window. There we go. So in our learn system here, I just did a search on the guides I'd written and then the filter for circuit Python. It gets it mostly right, I must have I'm not sure how that search works. If it's all keyword, we have a little category thing we click when we're building a guide, I think I saw a couple where it wasn't a circuit Python guide. But for the most part, this is I did the I did the math I have I think 96, maybe 97 now guides over the last few years that are circuit Python based. And this is the wide variety of things that that I've got here that I've put in. So we've got the touch deck DIY customizable TFT control pad. I promise you I'm not going to read all 96 titles. The Pip Boy there, you'll remember some mechanical keyboard projects, a bunch of different led matrix projects using matrix portal, got the Walkman, more keyboard keypad things. This one right here actually with the little animated GIF playing of the Bluetooth keyboard, this is a really, I think a really useful one for people who want to do accessibility type of projects, and other interfacing wirelessly with things like the iPad and iPhone works particularly well, I think you can also use this with Mac Oh, as I'm not sure on Windows, if it's as easy, but the ability to set up a microcontroller in this case, it's an RF 52 840 feather and send commands that are HID, just typing commands, it can also be media commands, so things like playing and pausing and volume. Here was this the sequencer project using reading a little disk with light sensors, a bunch of trellis m4 projects over the years, some neopixel things like lightsabers and goggles. That was the first Pico project there with that that board. That's just general. Hey, how do I use all the things that a Pico can do? More keyboards, more sliders, more LEDs, bunch of matrix projects here, some fruit synthesizer of some kind, drum sequencer, keyboard, a little unicycle bot. Here we had a bunch of projects. There was a box that had the cricket in it, and that had a bunch of robotics projects that I've done. There's a there's a flashback to a how much do we need to wash our hands kind of project. The flying saucer, there's our good friend Lars, he's made of circuit Python and love, I think. Walkman project, rotary phone dialer there. Got my Nintendo power glove as a wireless MIDI and that's actually also an RF 52 840 project sending MIDI over Bluetooth in this case. Chauncey, he does not belong there. Oh, no, he does. Yeah, I revised this guy. So this is my my plant watering robot. And he does have his circuit Python powered now using a clue. And there's our good friend pathfinder, the robot companion, Maypex Legends, Star Trek, L cars display, more phone stuff. I've got I've got a type. You can see it hacking holiday animatronics, some pipe portal projects there, more little turtle robots, sequencers, Minerva, the Ouija board. I revised the Lucio blaster to run this guy right here. Got a version of that that uses circuit Python instead of the original. Oh, God, Lars just took a dive. He'll be okay. Shake it off, Lars. Look cat MIDI keyboard, the hex pad, a little fun. See and say with Brian Kessinger there. If you saw the synth IO panel earlier, that's the Tyrell building synthesizer I had there. Some more telecom things, computer perfection synth and those to the PlayStation spinner controller and the ambient sound machine. So which is to say, there are so many different kinds of projects that you can do using circuit Python. And if you look at those chronologically, which that list didn't, you can probably see some of the features and things evolving over time. Because a lot of the times the projects I do are based on sort of the latest things that we've put into circuit Python that need testing or new boards that come out that need testing. If you want, MIDI Maniac asks what's the link to those projects? I'll just, let me go back to page one of it and I'll paste that there. There are a bunch of ways that you can get to, I just posted that over in the Discord, a bunch of ways you can get to this sort of stuff, but I just used a category and a keyword search. For some reason, the click on your name thing wasn't working. It's working again, yeah. So if you click on the name of a learn guide author, you'll see all of the guides that they've worked on. But I don't think you can do further search within that. So I couldn't filter just circuit Python. So I used keyword search. So there you go. Thanks circuit Python. And thank you so much for the community and circuit Python team and all the people out there working on it and libraries and their own guides that help me learn how to how to do the things I want to do and build the things I want to build. So let's see the project thing I wanted to get into for today. This one is a little bit more of a behind the scenes thing of something I showed earlier today, which is the fabrication of this case, get my finger right there. This case that I built to do the demo earlier today of some modules explaining how synth IO works. So in order to explain how synth IO works in circuit Python, I wanted to show physical real world synthesizer modules. And these are modern ones, but they might as well be the same as modules created in the 1960s. So that's a real fundamental basics of a VCO and a VCA and an envelope generator and a LFO and a filter. All of those things were what I wanted to show here with real physical modules. And those are all the things that make up how the chain of audio processing or of synthesis rather works inside of synth IO. You can get great clarifications on what I just said, if you head, head to our YouTube page and check out past shows, because they're all archives pretty quickly, you can already check out all the all the live streams from today. Go check that out. And Jepler and Todd bot and cat knee. Paul Cutler have all got great, great insights and things to say about how this stuff works. But anyway, I wanted to build a little case here and not probably too surprising. If you know how your rack is priced, the stuff is expensive, the modules and all the trappings. And one of the things about your rack, which is a standard is it has a standard mounting system, which is three U high, so three rack units high. And then the horizontal pitch of the modules can vary. And they tend to use an M three screw. Sometimes people use M 2.5, but they tend to use an M three screw. And so the whole spacing at the top and the bottom of these modules wants to go and get screwed into something like that. So if you go and buy racks, they tend to be expensive. And so you can build your own, you can do it as easily as just screw them into some wood. And I've done that for sure in the past. But it isn't as easy to move things around and and change your mind about how stuff's put together. So if you want to go to a down shooter, where are you? There's the down shooter. If you want to do it on the cheap, you can pick up this threaded strip, and they sell it in different lengths, typical one to find as a pair of them, because you need them on the top and the bottom in the 84 HP width, which is a pretty popular width. And then you need a way to mount them to whatever your box is going to be. And also stabilize them a bit, because at longer lengths, these can be a little bendy. This stuff can be a little bit flexy, which you don't really want because you're pushing patch cables in and pulling them out and you're turning knobs and stuff. So I wanted you can buy something that looks like have any, I think I have any examples here, looks sort of like 8020 or T slot aluminum with these strips, but you can't use the standard stuff because there's no room for the screw. So there's some very specific sort of track that this can go into. And by the way, a lot of this comes from server and rack mount equipment. So a lot of these standards, you'll find them in related worlds. So you can get rails, which is what they're called, which will be a strip of aluminum extrusion that'll have either sliding nuts, or these strips inside of them. And then you build your case around that. I've done that before that's a fun way to go, but it is still a little bit pricey. So I was able to do I think this was $20 to do 84 HP, two strips, and you can find it cheaper, you can find about $8 or $9 online for one strip as cheap as I found. One of the reasons it costs that much is that these are tapped for your screws. So these aren't just holes, these are threaded and that takes time on a piece of machinery. So these aren't the cheapest of the cheap. But once you get these, so in my case, it's about $20, I think I was able to cut them down to the sizes that I needed, I wanted to do I think a 62 HP wide for that box. And then I needed to come up with ways to mount this and build a box. So I was someone said no, I did actually want to try one. And I may still. But the and I tried some Lego brick creations, but that didn't quite work out the way I wanted to. So I went to the sort of tried and true method for me, which is to design something to laser cut. It's one of my favorite ways of doing this kind of stuff. So you can see here, I've got my I'm in Rhino here, I have replicated my threaded strip, including even the detail of threading that. Oh, hold on, let me just change the resolution of the screen so the camera is angry at me. Let me set my camera target. There we go. So you can see here, I've got unnecessarily accurate CAD model I made of an 84 HP wide strip. And then what I did was I kind of copied an idea I've seen before. coma electronics in Germany, I think they're in Berlin, have a case I have one of their actually two other cases that use this idea of whatever your front panel is, if you can cut out some U shaped slots that match the whole spacing here, you can place the strip underneath a piece of material and then the screws bind the the faceplate to the strip and to your module, which is probably easier to show in the real I don't know, I don't think I made an actual 3d model of that in here. Ironically, I just I just designed it basically 2d and laser cut it. So that's what an 84 HP wide case would look like. This is what my 62 I think it is HP wide case looks like with the telltale finger joint construction of someone who's getting ready to laser cut something or get get real busy with a with a saw. And so you can see what sorry, you can see I've got a faceplate and a bottom that basically match I've got a hole cut out from the center. And then I've got a front back and sides. And I made a little cut out here to place a DC port, a DC barrel jack connector panel mount so that I could plug my my power strip. So there's a power module, or power supply rather, and a distribution bus inside of the case so that all the modules can get plugged in because they each have a need for a little ribbon connector that gets plugged in. So what I'll do is I'll jump over to the bench and just pull pull the one I made here apart a little bit so you can see inside of that. Let me go to this view here. And I'll zoom in. You can see here, you know, this is what the acrylic that I've cut parts out from looks like I've thrown away some of the scrap but I've kept a bit here because this is a nice useful piece. Here's the middle. That was the hole that got cut out of it. So it's another nice piece of scrap there. And this in fact is the LED acrylic just because it was convenient and on hand. I didn't have enough material in one color. I have a bunch of different weird color ones and I decided to try to keep things somewhat uniform here. I also really like even though I'm not my intention isn't to do LED lighting inside of here. It's a possibility but it wasn't the intent. One thing I really like about this laser or LED acrylic is that it has a matte finish. On one side on the other side it has a fingerprint magnet which is the shiny acrylic. So you can probably that's not too bad. You see a big thumb print right there. So this matte finish just looks looks better to me. So I kept things simple by doing the finger joint construction those little tabs tabs and slots all around to essentially register everything and then I glued it. I didn't want to go and do captive nut and screw stuff. And I wanted to make it quick and easy so everything is glued but since I can remove the modules you can see inside of it. So what I'll do is try to pull these out pretty quick. You can see I'm not going to pull them all out at once because then the threaded strip is going to fall inside. There's actually nothing holding it in other than screws which is also how how coma electronics does their kits when you get one of their racks. As you can see here there's the inside view of the world there. I've got my power supply. There's a distribution bus under here. I'll show you in a second and then one of these ribbon cables is plugged in to provide power power and ground. This one uses 12 volt negative 12 volt and so positive 12 negative 12 and ground some modules none of them here but some modules also use 5 volt which is part of the specification but those will be a larger 20 pin connector for those. So if I pull that one out there I will now put a screw back in at the top so that's this is you can see zoom in the rest of the way there. So you can see my threaded strip is just underneath there screwed in from the top and there's really not a need to do anything fancier than that. You could find a way internally to secure that here cut a little slot and run the run the full width whatever you want but this works this works pretty well and again it wasn't very fussy. You can also see since I've got the clear ish acrylic there you can see how it runs just a little wider than than these oval slots that I put in place here. So that's now what's going to hold the strip in place as I pull out some more of these. Actually while I've still got modules in here I'm going to grab my power supply and turn it on just because it's fun to see what the LED acrylic does do with the the little power supply LEDs. This supply has I think colored LEDs on it for the different voltages. So if you see three I think it's three LEDs lit then you've got the plus 12 minus 12 and five volt are healthy. So you can see see the three of them they're shining through nicely. I kind of put a little blocker on the top of them a little scrap piece of acrylic because they were they were a little blinding but I see a blue a green and a yellow LED there which are telling me what's what's going on. So these look pretty nice through through the acrylic. So certainly you could do a light show big neopixel light show there. Plug that. Let's take off the next module here. By the way these are this iFixit kit of screwdriver and bits that we have in the shop is actually really I have a couple of these now and that's one of the features I love is this little ball bearing swivel top there for spinning the thing pretty fast when you're when you're doing this kind of stuff. So you can see there I've got my get a light on there. I've got a distribution bus of these IDC connectors in there. And again I'll just place a screw every so often to not lose the strip into there. I did debate using a latch of some kind for this top so I could just pull the whole thing off which is kind of nice. While I was building it it was kind of nice before I glued the top but I glued everything else to be able to just lift everything out to wire to place cables in and get in there and change stuff. Also sometimes you will find modules that have jumpers on the back. I think maybe maybe none of these do or maybe one of those do but sometimes there are jumpers for changing a range to go from negative five to positive five volt versus to go zero to 10 volt. Those are both things that happen inside of your rack synthesizer standard. Here I'm using these nylon M3 screws by the way on these modules and that's just to prevent from scratching the front of these. I also have washers on some of these here. So if you ever do dive into the your rack synth world or the module synth world you'll hear people talking about rack rash when they are selling modules that have been used. Sometimes there's dents and divots and things where the screws were in place there. Again this one has a FTDI dongle and a mini JTAG connector that you could want to do some reprogramming on if you were ambitious about it. I've bent one of those. So that's why sometimes you might want to pull things out and actually you'll see here as I as I remove these the the strip there is coming free. It's just one strip. It's not going to fall but you can see it kind of sagging there if I press on that. So that's not actually held in place by anything other than the screws coming in from above. And then I drilled out some holes on the bottom there to screw my distribution bus and my power supply. And then you can remove all of these ribbon cables. These ones are keyed which is nice. So you can't put them in backwards. But a lot of the modules are not for no good reason. So it's really easy to destroy modules that don't have reverse voltage protection. So you've got to be careful especially with DIY modules. But see that as far as I can take it apart because I glued everything but that is the basic design kind of my my version of the coma electronics case there. I've got two of theirs but they only come in 84 HP and I wanted a little smaller one that's still fairly deep. Sometimes you'll find cases that are very shallow. They're called skiffs and they'll work well for modules that aren't very deep but some modules are quite a bit deeper and so you need some of that extra room there to fit above all of the wiring and and distribution stuff. And then I've got my DC power panel mount plug there. That's what's running into this power supply. And since I didn't know exactly where I was going to put it I just left some holes. I put some holes in two other panels there. So those those are extra. You don't need them if you make your mind up before you put the rack together. But I could change my mind and put it on the back here. Sometimes it's a if you're up against other equipment you don't want wiring out the back and it's nicer out of one of the sides. So I was thinking there. So let me see if there's any questions or thoughts about that but that is my process there for putting that together. Oh good question. OK. So the question from SF Days. So does this project interface with any Adafruit hardware circuit Python. Yes. So I don't have it to show but in the past I've done some projects with a little circuit Python or circuit playground Bluefruit or circuit playground Express and created a simple LFO. That's the low frequency oscillator. So it can just be a sine wave or triangle wave of voltage which we can control the speed of it the shape of it the range of it. And with the little alligator clips we can use. These are really convenient actually for interfacing circuit playground Bluefruit with. See if I can find one here. Are you one of these. Oh I know I've taken them all out of here. We have alligator clip to mono 3.5 millimeter patch cable. So imagine this thing with two alligator clips on the end that you can attach to your digital GPIO output pin or an analog output pin and to ground. So in fact I'll I'll show you one of those real quick. Let's go to the shop. Mono. Let's just type mono. That won't find it. Mono cable. Here we go. So this is the one version of it. We also have the mail plug version of it. Which isn't showing up. Why not. Let's see. Mono. How about type in mono audio. That one. So one of those that's exactly the plug that all the Eurorack patch cables are. It's a mono. So just two conductor 3.5 millimeter. So that's how I plug things together. So for Eurorack there are many places where you can interface a board running circuit Python and one of the nice ones I find is to make a little LFO or other. Control voltage or gate output. So since the Eurorack modules are all just listening either for audio to run through in process or for control voltage DC or AC offset control voltage to tell the modules what to do. You can interface with circuit Python very easily. So that's my that's my answer on that. Otherwise it was just a behind the scenes on a workshoppy fabrication kind of thing. So that's what that looks like what that design looked like in in building it up there. Only half pick. What does that mean? Have I have I this my broadcast gone weird. Which half of what pick. Let's see. Cool. All right. I think that's going to do it then. We've got Scott coming up with a deep dive next. That's going to be in about 10 minutes. So I'll end this a little early today to give everyone a little break to go grab a snack and take a walk around the block and then come back and get ready for to have your mind expanded with a deep dive into circuit Python with Scott. And then after that we're going to have check my schedule. I believe show and tell at 4.30. And that's 7.30 sorry 7.30 Eastern time followed by eight o'clock ask an engineer. Oh someone told me that the the picture was only half of the cable I see I had cropped that off. There we go. That's better right. There's the full there's the full cable there. So those those are super super handy if you're trying to plug oscilloscopes into your synth gear and so on really really useful there. And since we're talking about the store let's talk about the discount Cirque Pi Day will get you 10% off in the Adafruit store. So head on over there throw a bunch of stuff in your cart. It's good for anything that's real physical goods. You can't use it on gift certificates or subscriptions or software but you can get stuff. If you are getting lots of stuff then you can take advantage of our freebies. So if you go to Adafruit.com slash free you'll see if we have any offers running. We got a bunch of them right now. $99 or more you get a free PCB coaster with the gold Adafruit logo. $149 or more you'll get a KB2040 keyboard. For $199 or more you get free UPS ground shipping in the continental United States. And $299 or more you're going to get a free circuit playground express. You can stack all of those. They just automatically do it in fact. There's nothing you have to do. So if you spend $299 you're going to get the freebies for and the free UPS ground shipping all the way up to including that one. So use that coupon code that'll get you 10% off. Buy a bunch of stuff get some of those freebies. Take advantage of those or don't. Just get what you want. Get what you need. And head on over to the Learn Guides for some inspiration. If you're looking for some projects to build. Oh that's good. Okay so someone just pointed out DCD thank you. Pointed out in the chat Scott's gonna be on at $230. So we have a we have actually a nice little break here before Scott gets started. So go you know live your life for a little bit and then come on back and and keep joining us for Circuit Python Day. Thanks everyone for coming to the show and to Circuit Python Day in general. I'll see you later for Inferred Industries. I'm John Park and this has been John Park's workshop. Bye bye everyone.