Power-cycling a USB port should be simple, right? (2017)
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Power-cycling a USB port should be simple, right? (2017)
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Re: Power-cycling a USB port should be simple, right? (2017)
#2Have a mosfet between the 5 volt regulator and the device. At 20 milliohm, drawing .1 amp, that's only 2 millivolt drop. Or, since it's a low volume design, just throw a relay in there.
Re: Power-cycling a USB port should be simple, right? (2017)
#3I had a need to test the insert/remove a whole bunch for a while. Because the timing worked out, I ended up getting a programmable USB hub [1]. It worked well for my needs, but I'm not sure I'd trust it enough for a really inaccessible location.
I do wish I could find a not stupid priced version of this concept that does USB 3.1
Re: Power-cycling a USB port should be simple, right? (2017)
#4I had a need to test the insert/remove a whole bunch for a while. Because the timing worked out, I ended up getting a programmable USB hub [1]. It worked well for my needs, but I'm not sure I'd trust it enough for a really inaccessible location. I do wish I could find a not stupid priced version of this concept that does USB 3.1 [1] https://capablerobot.com/products/programmable-usb-hub/
Took me a while to find this again, but here you go: https://www.yepkit.com/product/300110/YKUSH3, a 3-port USB 3.1 Hub with switchable Vbus that doesn't cost an arm and a leg.
Re: Power-cycling a USB port should be simple, right? (2017)
#5I had a need to test the insert/remove a whole bunch for a while. Because the timing worked out, I ended up getting a programmable USB hub [1]. It worked well for my needs, but I'm not sure I'd trust it enough for a really inaccessible location. I do wish I could find a not stupid priced version of this concept that does USB 3.1 [1] https://capablerobot.com/products/programmable-usb-hub/
Took me a while to find this again, but here you go: https://www.yepkit.com/product/300110/YKUSH3 , a 3-port USB 3.1 Hub with switchable Vbus that doesn't cost an arm and a leg.
Very nice find! Thanks a ton!
Re: Power-cycling a USB port should be simple, right? (2017)
#6Checkout this Hub Control library for C.
https://github.com/codazoda/hub-ctrl.c
I'm the maintainer, but I can only take credit for updating a single line, uploading to GitHub, and doing PR's (mostly to the README) every once in a while.
Re: Power-cycling a USB port should be simple, right? (2017)
#7I had a need to test the insert/remove a whole bunch for a while. Because the timing worked out, I ended up getting a programmable USB hub [1]. It worked well for my needs, but I'm not sure I'd trust it enough for a really inaccessible location. I do wish I could find a not stupid priced version of this concept that does USB 3.1 [1] https://capablerobot.com/products/programmable-usb-hub/
Took me a while to find this again, but here you go: https://www.yepkit.com/product/300110/YKUSH3 , a 3-port USB 3.1 Hub with switchable Vbus that doesn't cost an arm and a leg.
we use these in our CI/CD pipelines as we deal with embedded hardware. they work absolutely awesome for power cycling stuck USB peripherals or powering USB-powered boards for tests.
Re: Power-cycling a USB port should be simple, right? (2017)
#8Have a mosfet between the 5 volt regulator and the device. At 20 milliohm, drawing .1 amp, that's only 2 millivolt drop. Or, since it's a low volume design, just throw a relay in there.
The article links to a thread on the linux-usb mailing list where the author mentions he does sometimes resort to that.
It sounds to me like the author genuinely wants to have a discussion about some of the quirks in the USB protocol. I don't see anything wrong with pursuing all available options.
Re: Power-cycling a USB port should be simple, right? (2017)
#9This brings back memories from about a year ago when i was doing robotics.
Azure Kinect DK depth cameras had a firmware/hardware issue that would let it get stuck every now and then, and it would have to be power cycled. You'd imagine it'd be easy, but it was surprisingly hard. Ended up getting a new usb hub that supports power cycle...