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How does USB device discovery work? [video]

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Re: How does USB device discovery work? [video]

#21

Post by BugWatch »

AussieWog93 wrote: post #13
snakke wrote: post #6

Earlier quoted context omitted.

You're not wrong that the price of ram isn't that much these days. However, this is not simply a case of adding more ram and be done with it. There is a significant amount of extra engineering to be done. It would in the grand scheme of things be rather easy to "just add ram" but that's not how the product lines work for oscilloscopes. It's a bit like asking "Why does Intel price their high-end chips so high? It's no…

I have designed and commercially released an open source (USB) oscilloscope. There is absolutely no reason you can't just add more RAM (and a memory controller), or even add user upgradeable memory. If the big players don't do it, a newcomer will and they'll fall further behind the curve.

Could you provide more information, please? Thanks.

Re: How does USB device discovery work? [video]

#22

Post by AussieWog93 »

BugWatch wrote: post #21
AussieWog93 wrote: post #13

Earlier quoted context omitted.

I have designed and commercially released an open source (USB) oscilloscope. There is absolutely no reason you can't just add more RAM (and a memory controller), or even add user upgradeable memory. If the big players don't do it, a newcomer will and they'll fall further behind the curve.

Could you provide more information, please? Thanks.

I'm not quite sure what you mean.

There is no technical barrier that prevents an oscilloscope manufacturer from adding a DRAM controller to their designs, either via an IC or as an IP core in their main FPGA.

The cost would be relatively low, too, and long traces are extremely useful especially for beginners.

Market forces will work to make this a reality.

Re: How does USB device discovery work? [video]

#23

Post by randyrand »

megous wrote: post #9

I've recently been playing with CY7C68013A. Very approachable small USB (high speed!) microcontroller. With tiny amount of code, you can do quite a bit! It doesn't have flash and code is only loaded to SRAM over USB when you connect the controller to the host, so that's pretty flexible. So far I've been practicing on my saleae logic analyzer clone, which is based on this controller too, but there are cheap dev boards…

sounds interesting. Is it for USB device or USB host? Specs aren’t entirely clear.

Re: How does USB device discovery work? [video]

#24

Post by gsich »

AussieWog93 wrote: post #22
BugWatch wrote: post #21

Earlier quoted context omitted.

Could you provide more information, please? Thanks.

I'm not quite sure what you mean. There is no technical barrier that prevents an oscilloscope manufacturer from adding a DRAM controller to their designs, either via an IC or as an IP core in their main FPGA. The cost would be relatively low, too, and long traces are extremely useful especially for beginners. Market forces will work to make this a reality.

He probably wants a link to your scope.

Re: How does USB device discovery work? [video]

#25

Post by megous »

randyrand wrote: post #23
megous wrote: post #9

I've recently been playing with CY7C68013A. Very approachable small USB (high speed!) microcontroller. With tiny amount of code, you can do quite a bit! It doesn't have flash and code is only loaded to SRAM over USB when you connect the controller to the host, so that's pretty flexible. So far I've been practicing on my saleae logic analyzer clone, which is based on this controller too, but there are cheap dev boards…

sounds interesting. Is it for USB device or USB host? Specs aren’t entirely clear.

Device.

Re: How does USB device discovery work? [video]

#26

Post by megous »

thristian wrote: post #20
megous wrote: post #8

That's some fancy oscilloscope, but you can also get that info via usbmon, for example, directly to wireshark.

This video is a follow-up to a mini-series that started with examining the PS/2 keyboard protocol. The oscilloscope is there because the audience is already familiar with it, not because it's the best tool for this particular job.

Yes, I'm not criticizing the author, but it's good to know that you don't need fancy tools and you can get to see the enumeration too on your own devices, practically in similar amount of detail.

Re: How does USB device discovery work? [video]

#27

Post by throw0101a »

thristian wrote: post #19
rtrunck wrote: post #2

Ben Eater (Author of this Video) is fantastic. Learned so much on electronics and computers through this series https://www.youtube.com/watch?v=HyznrdDSSGM&list=PLowKtXNTBy...

Piggy-backing this comment to add some context for the OP video: This "USB device discovery" video is actually the latest in a series of videos where Ben Eater is building a simple 8-bit computer on breadboards. He hooked up a PS/2 keyboard as an input device, and then got sucked into a tangent of investigating and explaining keyboard protocols. - He investigates the PS/2 keyboard protocol: https://www.youtube.com/wa…

> on breadboards.

Whatever happened to wire wrap?

* https://en.wikipedia.org/wiki/Wire_wrap

I can understand BBs for quick prototyping and tinkering, but once you've settled on the design, I'd think WW would be less fragile to deal with.

Re: How does USB device discovery work? [video]

#28

Post by AussieWog93 »

gsich wrote: post #24
AussieWog93 wrote: post #22

Earlier quoted context omitted.

I'm not quite sure what you mean. There is no technical barrier that prevents an oscilloscope manufacturer from adding a DRAM controller to their designs, either via an IC or as an IP core in their main FPGA. The cost would be relatively low, too, and long traces are extremely useful especially for beginners. Market forces will work to make this a reality.

He probably wants a link to your scope.

Oh yeah, that was dumb of me.

https://espotek.com/labrador

Doesn't have an on-board DRAM controller, but I did look into the feasibility of it early on. In the end, I decided it was easier to just use the memory of the attached PC. Can record 10s of continuous data without dropping a single sample.

Re: How does USB device discovery work? [video]

#29

Post by balefrost »

internet2000 wrote: post #11

Is there a text version of the explanation?

In a sense... everything he covers is also covered in the USB spec. I can also personally recommend the book USB Complete by Jan Axelson.

Is there a transcript / blog post version of this 30 minute video? I don't think so.

Re: How does USB device discovery work? [video]

#30

Post by gsich »

AussieWog93 wrote: post #28
gsich wrote: post #24

Earlier quoted context omitted.

He probably wants a link to your scope.

Oh yeah, that was dumb of me. https://espotek.com/labrador Doesn't have an on-board DRAM controller, but I did look into the feasibility of it early on. In the end, I decided it was easier to just use the memory of the attached PC. Can record 10s of continuous data without dropping a single sample.

Thanks!
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