[011] USB Debugging with sigrok 

The Nyquist criteria applies to the frequency of the signal, not the bitrate. In theory you only need 10MSPS for a 10mbit/s signal, since a 10mbit/s stream of alternating 1s and 0s is actually only a 5Mhz square wave. But then again it's always a good idea to have a much higher sample rate than the absolute minimum.

I really enjoy watching debugging techniques videos. Thanks a lot.

Thank you for letting us have a look over the the shoulder of a real professional. High value content.

Fantastic, well prepared and presented videos. I now want to get Sigrok and play. Thank you.

As usual ......informative, detailed ,well thought out video and debugging thought process. Thanks for the video.

This is really an eye opening video for hobbyist I think. Thanks a lot! Please make more debugging tutorials with logic analyzer.

Greatest explanation I have ever seen about USB debugging. Much appreciated!!!

Brilliant Tutorial , very interesting to see the use of the signal bits moved about the code to narrow down the issue. very neat. An eye openning video from the perspective of someone just considering to use a logic analyser for USB development on a micro controller. usefull in so many ways, from explaining the D+ D- traces , using the decoders right up to the probem solving with the control signals. Thanks very much,

Very informative, thanks for taking the time to make this video !

Wow learning so much. Thank you for your channel.

Very instructive. I have had lots of issues debugging USB stacks in the past, and using the signal analyser for this task didn't come to my mind. Especially useful with USB parsing 😁

I have just found your channel and I immediately subscribed after the first video I whatched. Absolutely professional content! All the detail you put in, the easy to follow workflow, progression, the fluid, distraction-free talk is absolutely professional. Keep making videos, you should be at the popularity level of The Signal Path, Marco Reps, LiveOverflow, EEVblog and all the bests I may missed here!

Very nicely presented! I had to chuckle to myself when the debugging process begins as you're explaining how this can't possibly be broken! See, even after I remove my code it's broken 🙂! It's usually this step when the obvious error is exposed, and only the process of explaining exposes it. Here, you found a really interesting problem elsewhere. I really do enjoy watching the "directed problem solving" approach and demonstrating how that's much more effective than just randomly changing things and hoping for the best.. As much as anything else, that's the core lesson to take away when watching this. I found myself here trying to learn how to use sigrok and pulseview, and it was great to see this toolset "used in anger" rather than a contrived demo. Thanks for sharing that.

Excellent video buddy.

wow, what a fantastic explanation. Loving this channel

Very nice video. Shows the power of debugging software races through hardware techniques when you're close to the hardware. On larger systems where I've worked you're forced into debuggers or worse yet debugging through compilers (printf ugh!) . Heisenbugs become inevitable. Regards jla

Excelent video! Really awesome to see the power of open source software, scripts and command line in your videos, thanks

Amazing videos you gained a subscriber i love your videos :)

Nice to see you using libopencm3, I've started playing around with that myself as well. When setup correctly you can also run 'make flash' directly and have it call openocd directly for you, that should save you a few terminal sessions.

Now I know what Neo felt like in the Matrix when he had the training programs downloaded straight into his brain. I enjoyed this immensely, thanks!

This is extremely valuable content. I am really sad here because the channel seems dead. Please resume uploading such valuable content.

High quality content. Thanks !

Thanks for sharing. I quite like your toolset (esp. tmux and vi ;)

Nice debug! Thanks for sharing

Great video

Another great video, thank you. :)

Excellent video sir.. love from India

In the datasheet of the chip there is a timing diagram. Looks exactly like the output of the logic analyzer, the one with the slanted edges. There are time limits on by when you have to have your data ready to send it. And time limits by when you have to have your next bit ready to send. The same goes for getting ready to write the next bit... They are usually written out on the clock pulse, but the data has to be ready a little before. If you (or the code) get it wrong, the state becomes undefined and the Chip kills all communication. All serial communication Chips have the same necessary timing needs, always defined in the datasheet. There is a better way of explaining that I am sure, but that's the gist of it. You were pretty much right on the money with your timing conclusion. EEVblog has a great explanation in one of his videos.

Very nice video, TNX.

In your new printed circuit boards, in design you need to do all possible test points at once, further testing and debugging will become much easier, also in production it will allow you to test the entire circuit almost automatically. I always design two boards, the product itself and the response board with needles, also I often have another controller and the necessary peripherals on it to be able to automatically program and test my products. the same solutions are used by all serious electronics manufacturers.

Awesome, as always! A topic suggestion would be to set up an open enviroment for developing with ST and others ARM microcontrollers, I mean, setting the toolchain (GCC), explaining the build process (GCC flags, make) and GDB.

One tip: With openocd you don't need to specify the absolute path for the cfg scripts, just use these relative short paths: -f interface/stlink-v2.cfg -f target/stm32f0x.cfg

Great video! By the way, what is the name of the multiscreen development environment you are using that allows you to simultaneously have pulseview, editors, etc onscreen?. Thank you

I use nail lacquer and wire wrap wire for secure bodge wires, you can easily remove it with acetone.

Terrific work! Can you do a USB tutorial?

really great videos! off topic but how do you display a gui in a tmux pane?

Nice video's! I like that you support HW I have. I like that you support BTC. ( I dabbled at mining back in the day ) I like that sigrok download page has links to Slackware build info!

Hi, great lesson from you, please tell me how you started DSLogic-Plus in place with the Pulseview program? I downloaded from the official website of Pulseview for Windows 7 and it doesn’t work for me, but my native DSView_v0.9.9 program works fine, but I wanted to work with Pulseview, please tell me why Pulseview doesn’t see my logical analyzer DSLogic-Plus I have to do, thanks.

Hey where did u go? Really likedyour content

gold

Amazing video as always? Is it possible to capture the USB packets with 24MHz fx-2 Chinese clones? Or you chose DSLogic Plus Logic Analyzer since it support higher bandwidth?

how can I use a trigger with my cheap LA? Is it built into the software (PulseView)?

What desktop and terminal is that? Looks nice and I've been wanting to try a tiling window manager.

can sigrok filter? How can i check for non host packets without zooming around ( I cannot seem to zoom on osx with trackpad, it just goes all over place )

Yet another question, what kind of tmux are you using? I quite familiar with terminal one, but you have gui version of it.... which looks fantastic!

Can you tell me if i understood right or not. You can see packets send and received, but i cant have a device in between USB DEVICE and PC, to record captured packets and replay them to pc simulating me actually doing input on usb device, its not going to work as i cant just spam packets to pc and have same output as if i move mouse on pc or move Joystick ?

Hi, Which IDE are you using under Linux which supports openocd and debugging? I found quite nice STM32Workbench.

A gamne of chess, you say? Errr - no thank you. I'm busy. Hahahaha. Smart fellow. Excellent video. Thanks very much indeed.

Before you start writing code for STM32, first of all you need to familiarize yourself with all the errata datasheet (or even better, familiarize yourself with these at the design stage of the device, otherwise it may cause a new design), on the chip itself and also on the libraries used. They have a lot of errors, sometimes it takes a lot of time to search, and the problem is already described in the documentation.

Not being weird or anything but ummm i like your voice :)

could please share with us the version of sigrok you are using, i've purchased a DSLogic and haven't be able to use it with sigrok

By the way, what vim font do you use? 38:49

Does the little board provide a JTAG interface?

Hello. I have flash ROM for ground power unit. Boar have microcontroller NXP MK70 family. Plus help me in screening ROM from microcontroller and pls disassembly ROM in usb flash.

(WHAT IS THIS.. Just typed a very long reply, accidentally hit "previous page" now its all gone... Anyway, here goes again.....) So this is pretty interesting.. I've been having a seemingly similair issue with something I'm developing on a STM32F072.. Now it's not using libopencm, but ST's CUBE HAL libraries, and I've also added FreeRTOS.. The issue has appeared/disappeared, I thought I fixed it, then I didnt, etc.. You know how it is.. (So I don't recall if it was there before I added FreeRTOS, I think it was, anyway.) Overall I'm receiving data from the PC at about 25 Hz, and also sending at about 25 Hz.. I think the pipe error occured when I wasn't reading or trying to write at about 50 Hz, but did when I tried to make one of my loops actually 25 Hz.. It's been some time ago, so it's all pretty vague.. I kinda dismissed it all since it seemed like the issue wasn't present in the current firmware version. I thank you for this nice video, I can probably copy most of your steps trying to debug the issue in my case.. (Will see how well this'll work with my Logic analyzer, and equipment etc..) Looking at all the wires soldered onto your board, you probably should've added some more pads/things for debugging, no ? :p I've got 5 GPIO's routed to a connector on the board that are completely unused, though I have to admit, I will have to solder wires onto some USB data lines too... I will probably get back to you if I find out what is going on here.. But I don't see myself having anytime soon, unfortunately. Also, is that a 1.25mm to USB Type-A plug cable ? Darn, I need those! (with some strain relief..)

Hi Joel... I've just got hold of a wad of software that'd be brilliant if you covered it here. I've got hold of an AVR simulator ( github.com/buserror/simavr ) and a nice GUI for it to live in ( sourceforge.net/projects/simutron/ ) After taking a cursory glance it looks brilliant 'cus you can debug AVR code using GDB on Linux and not having to mess around with that nasty Windows stuff. But, even though I'm no stranger to GCC, I've shied away from the likes of GDB and QEMU and such like... So I'm here saying "looks nice but what the hell do I do". There looks like there's some coverage on RU-vid but, y'know, there's two kinds of RU-vid and there's more of "the other sort" than there is of "the good stuff".