 JP, it's time for JP's product pick of the week. We've all arrived just in time. Thank you so much for stopping by I'm gonna pause the little video re echo in the side there. That's gonna drive me mad mad. I say So what the heck is this all about? Okay, we'll talk about it Sometimes I use the AI inside of Photoshop to make backgrounds and thumbnails and boy is that one weird So, hey What's happening here? We've got people over in our chats. So thanks for stopping by. Thanks anyone Over on our YouTube chat as well as our discord chat if you're wondering where the chat is That's the place to check it out. That is at a to fruit dot it slash Discord and then you can look for the live broadcast chat channel right There that one you see that You can see my cursor you can't right there But that's it. That's the live broadcast chat channel. That's where people hang out during the live stream So go check that out if you're wondering where people are hanging out What else you can see I've got a Suspicious backdrop here because I'm prepping for the eight a box unboxing tomorrow night So come by it'll be at five o'clock Pacific time eight o'clock East Coast time same time as the normally Ask an engineer Wednesday show, but this is an ass a an eight a box unboxing takeover. We're gonna do So come by for that But I'm prepping for that so I've got a little backdrop situation happening What else so I've got a cool product pick for you today and You can go if you want to get a jump start head on over to that URL right there It's the product ID 5724 you can also Use your camera device to point at that QR code if you like that sort of thing That'll take you to the product pick and this show is being broadcast from inside broadcast right in there in the product page You can get it at a humongous discount, and you don't need a coupon code or anything like that You just have to buy it during the show. It's gonna be half off And we I think stashed a good good number of them before the show so go check that out I will tell you all about it in a moment and show you a little demo But before I do I will have lady Aida introduce this by jumping back slightly into the past take it away lady Aida The can feather So really I'm cranking out these RP 2040 boards with different peripherals on the right hand side I always wanted a board that had canvas built-in for easy plug-and-play No solder can projects and the RP 2040 feather is a great place to start that so It's got your classic RP 2040 chipset. That's a dual core Cortex M zero on processor nice chip We pair that with eight megabytes of Q-Spy flash. You'll use that for your program or your files That's kind of the middle top area there. You've got boot and reset button so you can do the bootloader and Reset button of course you can reset whenever you want. It's got USB type-c for data and uploading firmware and debugging LiPo battery built-in with battery charging through USB-C so you can take this project on the go There's a stomach UT port as well And then in the you know, the feather pinout is standard It's got you know, 21 GPIO pins and four more analog and two iSquared C ports and two SPI's and two UR so it's got a lot of stuff going on with it Great for use with Arduino micro Python or circuit Python and then what I did is on the right hand side I stuck a MCP 25 625, you know, like I've never heard of it. Yeah It's basically a chip that has inside of it an MCP 25 1.5 Which is a very very popular can controller plus a can transceiver It's just they just took those two chips and they squished it and they called it the 25 625 But the firmware you run on it is MCP 25 1 5 like firmware wise what the code you'd run for this chip controller is like the most popular can controller We've got Arduino code for it. There's circuit Python I think micro Python also has code for it pretty much any programming language is going to have code for that can controller Because it's the most popular one in the world There's also a little switch-capped boost converter Above it that'll generate the five volts so you can do can bus with five volt power because you use a five-volt power Sorry five volt logic Interface so the feather still running at 3.3 volts, but it has the five volt necessary to do that the can controlling There is a terminator a 120 ohm terminator Which you can disable by cutting that trace you need at least one termination on your can bus and then three terminal blocks low Ground and high so now you can plug into any can bus. There's a differential signal system your shared ground which is handy and then low and high and then you know Terminal screw on how many wires you want to shove in there and they're pre soldered So it's a new thing. I'm trying to get more boards where you don't have to do any soldering It's plug-and-play if you'd like to use it on a breadboard you can solder Headers that comes with this photo shows it. Yeah, we've tossed some headers in but you know If you don't want to use the headers you just want to do can you're ready to go and again We've got Arduino and circuit Python code and we also have you try F Which is a software that runs a firmware that runs on the RP 2040 and allows you to use your computer To connect a can device so it's like it acts as a USB to can bridge Which is very handy and then of course if you want to add sensors so you want to get can node with sensors There's thank you teaport you can plug in almost any of the many hundreds of Stem and qt or quick or picodev boards that come with the connector Yes, that's right. You can do all of that. Let me show you a little shot of it here I had to hide some of it because I've got it all connected up to some stuff I want to focus there for a second that is it right there And I will introduce it properly for you this Right here this that's my product pick of the week this week. It is the can bus rp 2040 feather This is a feather rp 2040 with all of the usual feather rp 2040 stuff that we love and on the end of it It has the can bus controller and transceiver built in so this is based on the very popular 2515 Controller, but it also has the transceiver built into it. So it's all on one package does everything you need The chip name and now I'm forgetting it because it's actually with those two things bolted together What's your name? It is the Yeah, so it's the mcp 25 625 which integrates the controller and the transceiver onto there You can see I have mine hooked up using these fuel office paper very convenient Screw terminals that we have there to my twisted pair for the high low differential signal as well as ground And what you do is connect that to other Can devices on your can network. So A little bit. I'll talk a little bit about can let's take a look at the product page and the the learn guide And then I'll show you a little bit of a demo in a second. So First of all, what is can can we associate it with cars? It's actually controller area network But it is it is a car an automate automotive thing initially And Oh, I'm getting a I'm getting a note that my audio is low. What the heck's going on microphones Let me know if that's a little better. I don't want to blast it out Uh, oh, I know what happened Okay, I'm not gonna mess with that thing there. Is that gonna Well, we'll see here. Let's let's goose this up. How about that? Yeah, that's getting close to zero db so the can is a Was originally designed as a way to cut down on the immense amounts of wiring inside a modern automobile I think this was in the 80s that this uh, bosh came up with this this Uh Technology so the idea is rather than having point-to-point sensors all heading to the front of the car Where you have a central Processing unit dealing with all kinds of different, you know, antelite braking sensors tilt sensors seatbelt sensors all of these things Build a network so that you can have a single wire that's running Among many many many of these sensors passing the data along You can use star topology. You can use daisy chain topology and it just cuts down on the immense amounts of wiring the way that the Feather rp 2040 can bus controller works is that we have the feather using actually on board spi connections to talk to the mcp transceiver and controller chip and then that is Taking all of the the messages in and sending out messages can go both directions to any other devices any other can devices on the network I was uh Previously I was thinking that one of the main uses for this would be car hacking and someone asked. I think it david david glau de david glau de in our chat asked about Using this for reading like from your odb 2 port Certainly that I believe is possible with this. It is able to speak can The Thing is it's actually useful for a whole slew of non-car and non-car hacking things because it is essentially A way to network devices that is Much more electrically robust than spi or i2c has much longer wire runs than those you can do I believe it is 120 feet in a One megabit per second and you can get Like a thousand meters long if you're dropping it down to like 50 kilobits per second So depending on your needs you can really send your data a long long distance with great Integrity it fights noise by being a twisted pair differential. So the messages have a high and a low. That's what those two Terminal positions are other than the ground is that when it wants to send a zero It goes high on the high and low on the low and then comes back down So there's some some noise essentially cancellation going on there. You're not As worried about little voltage spikes. It also counsels out electrical interference. It doesn't send out Interference because those are equal and opposite waves or differential voltage signals on them. So really really robust You can Connect up multiple of these And have one that's kind of your main unit, but they can all talk and listen Yeah, deba dogs has used an aircraft using a lot of robotics applications But anytime you're thinking hey, I kind of need a long run of a couple of or many more than a couple of microcontrollers And sensors talking to each other. This is certainly worth considering The let's go to the product page here for a second You can see here. It is 50 off today. So nine dollars 98 cents That's I think the price of a regular feather, but you're going to get it with the regular feather rp24, but you're going to get it with the controller and Terminal block on there to do all of the can bus stuff. So why not? It won't interfere in any of the regular feather stuff But if you're thinking of picking up some feathers, maybe get one with a with a can bus or get a couple of them So you can talk You can see here if we scroll down we've got Some links with info about this. We have a link down here to the learn guide so if you click on over Here, this is the main learn guide. Liz Clark put this together. Thank you, Liz. We have Pinouts for power management. You can talk to it in circuit python. You can use micro python You can use arduino. We have setup instructions and examples for using psych with circuit python and with arduino Here's a an example here the can bus test You can also test stuff in a loopback mode So it'll send and receive its own messages if you don't have multiple devices It's also a lot more convenient for for setup versus two Circuit python devices plugged in at the same time and you're trying to write to them You can do it, but it's it's actually kind of nice to be able to Program just the one on its own The Let's see. Yeah arduino same sort of thing. We've got a can bus test that you can run in there You can also go down to the downloads page and here is the Um data sheet for the controller from microchips mcp 25 6 2 5 which has that 25 1 5 Controller in it as well as the trance ever and this will give you some of the info about operating temperatures speeds I think the wire Run distances may be also in here as well, but that's an easy one to google So this will tell you In great details an enormous data sheet in great detail everything you need to know 90 pages long So if you need to know it, it's probably in there But what I thought to do is give you a A little example of a couple of these talking to each other. So what I've set up I'll go to my Down view let's see. Yeah, let's go to this Let's go to this configuration actually Not that that okay So you'll see here. This is the one I was showing before This is a How I have that set up so I can get it enough out of the way um, so this is the Settle light here. This is the feather. I've got uh three wires coming off of it I happened to just cut the ends off of a cat 5 cable and I'm using some of the wires from that Uh, just requires three wires and I've also got over stemma qt See we've got the little quick stemma qt port there I have a rotary encoder plugged in stemma rotary encoder and then this is actually a pretty long Run of of wire here. This is I don't know 20 feet or something like that. Uh, no problem. So that's running to second feather rp 2040 can bus controller there. I'm just going to weigh down this Table so it doesn't go flying away. Uh, and on this one I have an OLED screen So this will show us data coming from Uh, the first one here. So if I step back, uh, and you watch the screen there It is receiving messages. I just have it sending the Incrementing or decrementing of this rotary encoder that's built onto there You can also see it is listing the address. So these, uh, you give them unique addresses So you can filter things you can prioritize things based on which Can device on your network is doing the talking And uh, this is you can see Got no problem whatsoever with incredibly Long runs and it is super robust. It's not dropping any messages there. That Is one of the huge benefits of the can network Let's see What else so here here's some nice close-ups you can take a look at there The benefit that la more mentioned of having it essentially be solderless is that you can plug in power to it You can plug in a battery. You can see on this one I've got a little lipo battery neither of these are actually plugged into usb right now It'll charge the lipo from there because it's a feather and You can plug in stem acute devices over that stem acute teaport to add sensors knobs displays And you can plug in your Three wires for the can bus using those terminal Connectors aren't there so no solder necessary Of course, you can solder it if you have a have a project that needs that but it's actually Essentially plug-and-play buy it Screw some things into there into those screw terminals give it some power Code it over usb and off you go This could be Many sets of wires coming into any of those ports. It's it'll just daisy chain along You can set up little wiring hubs if you want to but there's no There's nothing no router necessary of any kind. They are able to daisy chain or able to star Configuration the wiring we could have plenty of wiring spliced along the length of this going out to different controllers. So Really really neat protocol And mic ps this is yeah, you could use any three wires Twisted pair is what they specify for Best reduction of any kind of electrical interference. I happen to be using a cat five cable that I cut the ends off of But you can use Three wires is all you need to connect those up And an ethernet cable is is a really good choice because you probably have tons of it laying around Does not need to be shielded So you can get away with cheaper lighter easier to deal with easier to bend wiring because the twisted pair and the differential signal takes care of Any noise problems you might have so it's a Much easier than if you were having to deal with using a shielded cable Nothing fancy there And you can of course also get away with just using three wires of pretty much any kind as you get to longer lengths or in More electrically noisy environments such as inside of a car or a robot or an automobile Then you you probably do want to go with the the twisted pair for the data Other questions does the gauge wire have a bit of calculation for the total distance What would you say the best size wire is I do not know I would google that I am a newcomer to canvass. So I really don't have I don't have any info about the the best possible gauge for that Rufus mentions you can also actually just use two wires all paralleled. Yeah, I think the ground is a Is a nice to have but I don't think it's necessary. So I think you can just do the high low differential Um Yeah, Todd mentions you could use old phone Twisted cable pots cable as well since you only need three or four cables So a couple pairs of those plenty plenty of options lots of good diy options given the fact that you're using either cat five cat six Phone cables are really good options Uh What else any other questions? Uh, yeah, it's got those nice oval reset buttons these cute little Buttons right here that you can use as a User button once it started a boot button for initially getting into the boot loader Reset buttons a reset button. Uh, we've got some neopixels on there I used that just to help myself distinguish between the two boards one's purple one's Bluish so I could tell which one I was doing stuff on in my code And let's take a look actually at Some code right here My code window And I'll plug this one into a usbc so that we can Look in the repel there Disco tool disco tool actually Yeah, that code's fine. We don't need to resave. Um, so if I send Messages by twisting this one now from wherever I want it could go all the way across the workshop You can see those those messages coming in which list this guy's unique address and then the integer of What my rotary encoder is doing? So looking at the code here you can see the library is Adafruit mcp 25 15 So again, that's the name of the controller even though this chip is the controller plus the transceiver bolted together The library is still the 25 15 adafruit underscore mcp 25 15 Can i o importing message and remote transmission request and then From the 25 15 library importing 25 15 as can Set up here. I've got my spi bus Set up and then i'm creating the can bus with can on spi told it what the chip select is Right now loop back and silent are false You could turn those true if you wanted to just have messages sent by one looped back to itself during testing And then i'm using i2c only because of this Screen this little led screen on here. That's not necessary for using the can bus With that set up all you do in the main loop is with the can bus listener Look for messages. So the message count equals listener in waiting If we get a message then i'm taking that message and i'm just sort of unpacking The message into a readable format so that I could print that address and that number there But this there are some nice example code Nice code examples in the library you can check out you can Do the basic example of send and receive you can have just a receiver just a sender And then a few I believe more advanced examples involving interrupts It is possible to have some messages Come out on top really important for cars you want things like anti-lock breaking to Send their messages with priority over a headlight controller for example So you can do certain filtering and prioritization in can I just haven't done that. I don't really know how that how that syntax looks, but those are possibilities within can itself Let's see any other questions There's a nice Link let me bring up my discord here that liz put up to a project from calling furs furs Super famous youtuber whose name I can't remember he pronounced His project of a Some sort of vehicle contraption there is using A can bus to communicate among things. Yeah, I've seen projects online of Can bus used for non vehicle things for example Someone who had a hackaday project with some solar panel metering Used can to talk between a sensor and a raspberry pi So there's a lot of possibilities using this as as a communication method between your devices All right, have we done it? Do we have any other questions? I think That'll probably cover it. I said all I have to say. I think so So yeah, let's wrap this up That Right there's my product pick of the week this week. Are you upside down? You're right side up That's my product pick of the week this week. In fact, let's uh Let's show two of them. That makes the point, right? This is a network Product pick of the week this week. It is the feather rp2040 can bus Freighter for industries. I'm john park and this has been jp's product pick of the week. Bye