I don't have a hackaday account. But, I just wanted to clear up some confusion a poster over there seems to have, just in case you got some ideas about what this video was going to show you based on what you read there. Or you found this video yourself and also came to the same conclusions they did. Or were about to to come to these conclusions. They seem to have gotten the point of this thing backwards. So, it's strangely easier to clarify things in reverse order. Starting from the end: "He runs through a few other potentially useful scenarios, but really, the best use of something like this is to educate yourself on the lowest levels of USB connection negotiation". *_The whole point_** and really **_only point_** of the board shown **_is_** to demonstrate the first (low level) thing a USB device does to signal for attachment, which in turn causes it to list in the mentioned utilities, in the way shown.* That is, the minimum thing that a USB device has to do right to cause that to happen, namely USB device pull-ups. The point _is to educate yourself on that topic and hopefully have that inform your debugging of USB device problems._ Or you can just find it mildly interesting. The board you see in the video was put together to help demonstrate the device pull-ups and nothing more. That "best use" was the _only intended use_ for it. *_"[TM] points out, you could use this circuit to test that the physical port on the host at least minimally works."_* You could use it that way. But that's not what I'm explaining at all. What I'm showing is what you can expect to see on your computer (in both Windows and Linux), if something successfully creates these signals alone. These signals are the minimum needed to list in same way in both Device Manager and dmesg. That's what I'm showing in the video. *_"as this extremely minimal but functional USB device illustrates."_* Well, the board is somewhat minimal. But, as many people pointed that you don't really need an actual linear regulator IC on it (more on that below). However, this is definitely not anything _I_ call a "functional USB device." It quite literally reports with failures to read the device descriptor and has nothing on it capable of sending USB messages, which are both things mentioned in the video. What it _is_ is a demonstration of the "minimum needed for a USB device to list in Device Manager", hence the video title. So far as I can tell, the author thought the material at the end of the video was intended to describe ways to use the board shown, as though it were made to be a tool you could build and not what it is, a demonstration board. What's being talked about at the end of the video are ways you can use "this understanding"... understanding of USB pull-up resistors. These are the "something useful" I mentioned at the beginning of the video, the "something useful to use in your thinking when troubleshooting USB problems." Ways to use the under "understanding". *Not* ways to use the board. I hope I'm not coming off as mean in the above. I'm glad someone was thoughtful enough to mention it on a site about electronics. It's crazy to me than anyone is watching this. I thought like maybe 5 people would watch it, maybe 50. But so long as people are watching it, I do want to make really clear about what is being said in the video and what is not. It is just demonstration and description of a basic thing that USB devices do and how you might use the knowledge of that which is demonstrated to help you in troubleshooting. Regarding regulators and dividers: Mostly I used a regulator to be more or less in analogy with what you actually find in USB devices. They're typically already 3.3V devices powered by a regulator. Or they're 5V devices that have an internal 3.3V regulator specifically for this purpose. And it's probably the least distracting thing to put there when you're explaining something not-that on the board. I'd also briefly considered using what the Digispark uses, which is essentially a zener regulator and because it features later in the video. And because I also happened to know where some of my zener diodes were. But, I also just had a regulator. And yeah, you could also probably just make a divider from VUSB to GND. I didn't try it. I expect it works. But also I simply had a regulator and cap at hand. Could you use a divider? Yeah probably. If you wanted to rely on the 15k internal pulldown you won't wind up with 1.5K on the top. You'll need something more like 8K, I think. Which is not what is called for. Would it work? Probably, I think. If it worked for me would it work for you? I don't know. Maybe. If you put 1.5K on the top with only 15K on the bottom you'll wind up above the 3.3V nominal signal range. Is that a problem? Maybe not. If it wasn't a problem (perhaps damaging something) for me would in not be a problem for you? I don't know. So, you'd need a resistor in parallel with the 15K internal one, which is quite large compared to what you'd need externally. So you can more or less ignore the 15K and you don't necessarily need to run the parallel resistor calculation and just think of it as simple two resistor network. If you put a 3K resistor on the bottom of the divider that should be about right. With 1.5K on the top it divides 5V to about 3.3V. Would that work? Probably. However, the USB host is going to act on that divider when it tries to set a device address and ask for a device descriptor. Is that a problem? I don't know. If it worked for me, would.... Or you could just use a regulator. And then it will work and immediately be recognized as something that will work if you were trying to explain it someone else, say in a video for example. =) If you want to play with voltage dividers or the Digispark/V-USB/bitbanged style zener setup, go for it. If you have TL431 kicking around, I'm sure you could get that to work. Or if you have a simple 3.3V fixed output linear regulator kicking around, maybe just use that. If you're not worried about the repeatability of your setup you have a lot more freedom. Try stuff way out of spec. I did and found at least on hubs that I tried it on it worked fine to get similar results. But, you can get a 3.3V regulator like for under 1USD, in quantity one, at least if you're in the US ordering anything from a US parts distributor. Original Message: I'm really surprised to find this sort of support. Especially on a video like this. Had a little more to say about it in a community post. But mostly I just want to say thanks for letting me know you're getting anything out of watching this. It's just good to see. ukposts.infoUgkxvMno3tHF9bHJ4N3BiNBrIeZPUuBtQZWF

Plot twist: there was a tiny microcontroller hidden inside the electrolytic capacitor package.

The internet needs more videos like these that help to demystify what have become everyday technologies an help the folks trying to utilize it to develop some basic debugging \ troubleshooting skills.

This video is incredibly helpful to quickly narrow down on some USB problems, thanks for condensing all this information down!

Great video! One small thing I caught: at 4:20 you say that SuperSpeed also pull up D+ to initiate the connection, but this is not strictly necessary. A SuperSpeed connection solely uses the SuperSpeed wires, so it'll even work with D+/D- completely disconnected. This allows for fun stuff like attaching a SuperSpeed-only and a *different* Low/Full/High-Speed device to the *same* USB port!

Got this video recommended to me in my feed. I wasn't looking for this, nor do I have a particular use case for it at the moment. But watching these well explained videos of small creators always reminds of UKposts in it's early days where you got recommended all sorts of random videos because the algorithm wasn't that specific. Keep up the good work!

TM -- I have to commend you on a meticulously conscientious lesson in basic USB. A great job on focusing on the essentials that implement the basic functionality. And lovely attention to details that help everyone keep up, like having all the connections on the Veroboard on one side, and pointing out the number code on the resistors. Well done!

Good stuff all the way through. I'm really impressed with the illustration quality and thought that went into this video, I know that's a lot of work!

Subscribed. You explain stuff flawlessly. Full of details, visual references and without overcomplicating it. I work as a technician and these type of videos are gold.

Comprehensive, detailed, simple and informative. Thank you for taking time to explain this. It will undoubtedly help in troubleshooting USB related issues for me.

11:31 instead of being pulled to 3.3 volts, it's pulled to 5V across a 1500Ω resistor. The whole 5V to 3.3V conversion is based on resistors and zener diodes. The necessary code for USB is controlled by bit bang software.

USB C specs also support the “Audio Accessory Mode” so you can make a mic input and speaker output without even using adc or dac via USB

At around 7:00 when you say the “system sees the pull up resistor” I would change that to the “the USB controller sees the pull up resistor and reports to the system”. Minor semantic change but it would maintain the different layers appropriately separate. Thank you for the great video!

Extremely good content, I had no idea it was so simple to have the OS see the device. Subscribed!

This is a wonderfully digestible video, yet also very comprehensive. Great job, and this is going to help a lot of people

Not only is the content very well presented, but the production quality is exceptional. Thank you TM.

This was an amazingly explained concept and a joy to watch!

Next, grab the D+ and D- switches and manipulate them so they are on or off for roughly 570 ns with the following pattern...

That was very useful, thank you. Let me also take a moment to appreciate the beautiful weathered wood background! I used to keep old siding boards around just for that special look.

The algorithm has blessed me in this sacred night with a gift from the internet gods. 1k subs? Sir, let me up that by 1 right now.

This is an insanely well made video showcasing a clever thing. Kudos to you!

In my dreams you now start a video series, where you build any simple usb device on a breadboard level. It is not everyday when you love YT algorithm for showing a top notch of the top notch-quality video. I had to watch this 3 times to make sure I learnt every piece of details given in this video. The outcome was to find just one reason more to hate Windows, lol.

Very nice demonstration of how the USB device detection works.

thanks for this video! I didn't know the first level of USB detection was that simple.

This is helpful in so many ways: Linux & Windows device debugging, electronic circuit for USB connection, and more. Thanks 🙏

What a great video! Thanks! Your explanation is clear, to the point, and well explained. Love to see it. Gonna check out your other vids.

Wow this is incredible! Thanks for taking the time to make this video!

What an amazing in-dept explanation. Thank you!

Ah, never thought of that before, I always thought it was digital devices talking to each other - very useful and informative! And I did read your channel description by the way!

This is such a great demo! I absolutely have a better understanding of how USB works now. Thank you!

So amazingly explained and in a simple way! Especially 2:20 - 4:00 ! Thank you!

Great video! I love to see how the low level stuff works. It always helps in obscure diagnostic scenarios.. Thanks!

Thanks. I appreciate people, who know,what they are talking about. I learned a lot from this video. Greetings from Germany.

Great video. Love knowing how pulling high or low on the data line hints the capabilities of a USB device and that it wants to communicate but also how the address is handled next by USB controller drivers. I often see "Device not responding to setup address" with flimsy USBSATA adapters or bays and eventually they figure it out. As if the USB chipset is quick to wake up but the storage controller isn't. If not some other issue involving the cheap design of those ones.

For screenrecording (preferably with OBS) you have to choose the option "indistinguishable quality (very large files)" to get crisp recordings. (the files arent _that_ big)

This video is excellent. Very clear. A video that paints a thousand words kind of thing.

Love this kinda stuff. Learned so much, will help with my development in the future 1000% Thanks for making this!

This is such a great educational video! Love the idea, explanation and video style!

Didn't have any reason to click on the video other than to learn, and I wasn't disappointed. I think it will come in handy if I ever get around to making my breadboard computer. Subscribed and look forward to learning more from you :)

great video explaining something i hardly thought about! excited to see what else you make! keep up the hard work ! :)

This is very neat, it’s cool to see a video like this become so popular despite a low number of subscribers

Thank you for this informative video. I've been wanting to learn some of the USB fundamentals, starting from the ground up. This definitely started at the ground! I'd love to see something similar to this that shows the minimum messaging needed to send a minimum Device Descriptor in order to clear the Unknown Device error.

This rocks and helps remind us that sometimes we overthink things.

The thumbnail + naming of the video are perfect

This video is very clear and answers some questions I've had while tinkering. Thanks so much, excellent work. I would watch anything else you put up that covers the basics of how USB and microcontrollers works. Or really any other low-level computer engineering topics that don't assume a BS in computer engineering :)

I don’t do much work with microcontrollers but this video was very informative and easy to understand, definitely will be a bit more aware next time I have to troubleshoot.

Thanks for this video on USB. You've helped to lift the lid on the 'Dark Arts' of USB. Looking forward to more interesting videos from you.

Very nice and to the point video. Really helpful. Thanks a lot.

Great video and great explanation of the USB signals

Very good video about the lowest-levels of usb connections.

This is absolutely helpful and great video! It would have taken days to google and learn these information by myself. You have just explained everything in minutes. Subscribed for more videos. Thank you!

This video is a masterpiece of clear and cogent explanation. Thank-you.

Glad this showed up in my recommended. As a computer nerd with 0 knowledge about electronics, this will come in handy when troubleshooting usb devices. That process can become frustrating very easily when stuff like this is perceived as "magic" by a noob like me. Great explanation :)

Great video. I was holding my breath waiting for you to explain what happens if switch both the D+ and D- resistors into circuit...

Awesome! Please do more USB hardware and software videos like that!

this is brilliant! and the video presentation is outstanding. bravo!

The video is amazing, my mind is blown away. Maybe in the future i will make a usb sound card. I never knew how a usb is conected, now i do !

great video. clear, concise, and informative.

Thanks for making this. I love it when people show how much magical/cargocult/misunderstanding in thinking there is in common online advice for computer problems...

Extremely insightful! Thank you

I had a good laugh imagining you mashing the switches cartoonishly to send a device descriptor

Sir, you got style! Realy good presentation. Thanks a lot for this video!

Thanks for the info! It's amazing to me that I can have BSEE and never have learned this.

Wow thanks, I had no idea a connection could be that simple.

I always wondered about this, so this was interesting. Thanks!

Today I learned about "new messages" and "time delta" in dmesg, too!

Both useful and entertaining, thank you!

I wanted to do this experiment for sometime. Thank you.

This kind of increased my respect for windows. The diagnostic message in the device manager is cool

Thank you for an amazing and interesting video!

now this is quality content. thanks for making the internet a better place!

Thanks, interesting that DM shows it that early, but I guess it makes sense to allow the diagnostics you have described.

God what a great video! Please continue making videos- they're great!

Just wanna let you know that I think this is super cool and I'm gonna finish it tomorrow, since it's late as heck. It's always nice to see some low level stuff like this, and without a formal education in all of it, it's hard to find good resources.

TIL Wireshark can be used to monitor USB traffic. This is frickin cool. Thanks for sharing!

that is honestly actually really interesting

This video has blown up - can't wait to see more! USB is still a black box to most of us Arduino developers. I learned something.

This is an awesome video explaining it simple detail! Hat's off mate! I think I'd waffle on too much explaining the same thing.

Excellent video and very interesting! Thanks!

You somehow managed to explain in a way that my Aspy brain understands completely 👍

Well heck, learned something new today. Thanks for that 👍

Please release your next one as soon as possible. This stuff is fascinating ! (and I'm not being sarcastic)

Brilliant video! I learned a lot of new stuff :-)

Yes, very useful information! I'm not in IT but everyone at my work knows I'm technical so... well, you get it.. This is new information for me and I am positive it will help me out on more than one occasion to come!

No idea how I landed here but thank you for the amazing content

Wonderful video! Thank you very much!

Truly one of the divices of all time

This video helped me to have an idea what happened to my CH340C yesterday when I finish populating my board components and tried to plug it into Windows 11. Got exactly the message shown in this video. The message was not very helpful to me until I watched this video. I resolved the issue though and the serial chip was recognized but this was a eye opener. Thanks.

Excellent explanation!

This is really helpful! Thanks!

really informative video i might try to make this myself more fun that way

Thanks for the upload.

Very useful info. Thanks!

This is great! Really helps demistify USB a bit. Now I'm curisou of whats the minimum for the device to acknowledge its bus address, and maybe show up with a name 😄

Clearly and logically explained!! Sub'd!!

Outstanding info .. Very good to know .. Thank You for sharing ... Cheers :)

Thank You for the content!

I learned a lot. Thanks.

This is very interesting stuff. Had no idea USB device detection was so simple.

Very cool, thanks for sharing your video! (subbed)