Re:Hacking together a USB-C charger for a cheap Chromebook
by ogre_codes on Monday October 12, 2020 @12:27PM
(#24756121)
The title is a bit of a misnomer. They hacked a laptop with a barrel adaptor power supply so they can use a USB-C charger with it. So the issues dealing with USB-C PD aren't really there. (Or exist in the reverse which I suspect is more tolerant?)
Re:Hacking together a USB-C charger for a cheap Chromebook
by nudgeee on Monday October 12, 2020 @10:58AM
(#24755013)
In order to carry the USB logo, chargers/cables/connectors/etc must pass a suite of compliance testing to get certification. Specifically for USB-C, you can find details of the USB Power Delivery 2.0/3.0 Compliance Plans at https://www.usb.org/usbc. This of course does not stop cheap knock-offs being made without proper compliance testing.
I think as long as these hacks stay in 'prototype' mode, and is clearly called out as such, then it is fine. Once it goes beyond that (ie for sale without proper testing, etc), then it gets worrisome.
Re:Hacking together a USB-C charger for a cheap Chromebook
by gambiting on Monday October 12, 2020 @05:04PM
(#24759421)
Nintendo Switch has the official USB-C logo on the box and it's not compliant, in fact plugging in the "wrong"(but also USB-C compliant) charger can break the device.
Re:Hacking together a USB-C charger for a cheap Chromebook
by Dylan16807 on Monday October 12, 2020 @05:58PM
(#24759918)
The only chargers to break the switch were putting 9 volts on a low voltage data wire. Definitely not compliant.
The switch has a couple issues with how it requests power but they're minor and mostly on the dock rather than the actual console.
Re:Hacking together a USB-C charger for a cheap Chromebook
by OJFord on Monday October 12, 2020 @11:32AM
(#24755442)
The way around it's done in TFA though (adding a USB-C port to a DC barrel) seems least risky thing you could do to me - assuming you're using a known-good standards-compliant supply, you're only relying on the 'PD trigger' board requesting the correct voltage. Could add OV protection or a regulator if you don't trust it.
Re:Hacking together a USB-C charger for a cheap Chromebook
by Dylan16807 on Monday October 12, 2020 @05:56PM
(#24759903)
> The reason why he was doing this became clear when one of the cables he tested was so bad that it fried the USB port on his Chromebook Pixel 2015.
Nnnnnnot really.
He was checking for cables that were misrepresenting themselves and might cause the wrong amount of current to be drawn.
He found one cable that had the power wires completely backwards. That means it was a very blatant mistake that could just as easily happen to any kind of cable.
The reason why he was doing this became clear when one of the cables he tested was so bad that it fried the USB port on his Chromebook Pixel 2015.[0]
[0] https://www.androidpolice.com/2016/02/02/google-engineer-ben...