It could be done but not with only one resistor - you'd need both and both would need to be not connected to the Pi4 USB-C socket (as that would short them together, rendering the adaptor useless)
It's all written in the post with the picture.
Re: Timeframe for USB C power board revision
55:55:44:44:4C
52:4C:52:42:41
Rose tinted glasses are difficult to see through.
52:4C:52:42:41
Rose tinted glasses are difficult to see through.
Re: Timeframe for USB C power board revision
You wouldn't need to do that with an external adaptor. Just cut one of the two wires in the USB and connect that via the one resistor to ground instead. That way it won't matter if both are connected together on the Pi, as one of them is no longer connected to the cable.
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Re: Timeframe for USB C power board revision
The only problem with the one resistor adaptor is that the other CC line will still see two resistors in parallel -- so half value. I have not checked to spec to see if that is within tolerance. If not, it is possible that the cable would work with the plug inserted one way round only. Nightmare!
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Re: Timeframe for USB C power board revision
0.5g is not small amount of salt. Come on - we need USB boot fixed! Oh, sorry - wrong topic!
Or, should I start with 'take it all with pinch of salt'?
Now seriously:
Would someone be able to make some post/blog with pictures of how-to? Diagram - which pins (wires) to be cut so such resistor can be added. I have spare Apple adapter for that, one off operation (two SSDs on two USB3 ports on one Pi4). I am happy to source and sacrifice cheap, short USB-C to USB-C cable for operation...
Or, should I start with 'take it all with pinch of salt'?
Now seriously:
That seems quite a good idea. Original PSU cannot get two of SSDs powered at the same time and I got an itch to try to rsync one to another and thus kickstart another Pi4 machine (not 100% sure what for, but I have it and why not?!).rpdom wrote: You wouldn't need to do that with an external adaptor. Just cut one of the two wires in the USB and connect that via the one resistor to ground instead. That way it won't matter if both are connected together on the Pi, as one of them is no longer connected to the cable.
Would someone be able to make some post/blog with pictures of how-to? Diagram - which pins (wires) to be cut so such resistor can be added. I have spare Apple adapter for that, one off operation (two SSDs on two USB3 ports on one Pi4). I am happy to source and sacrifice cheap, short USB-C to USB-C cable for operation...
Re: Timeframe for USB C power board revision
Figure it out for yourself. Top left corner of https://www.raspberrypi.org/documentati ... educed.pdf and https://en.wikipedia.org/wiki/USB-Cclicky wrote: ↑Fri Oct 25, 2019 2:24 pmWould someone be able to make some post/blog with pictures of how-to? Diagram - which pins (wires) to be cut so such resistor can be added. I have spare Apple adapter for that, one off operation (two SSDs on two USB3 ports on one Pi4). I am happy to source and sacrifice cheap, short USB-C to USB-C cable for operation...
Quis custodiet ipsos custodes?
Re: Timeframe for USB C power board revision
and you think that's gonna change something when you use a 'apple PSU' (it's not only apple, they're just the famous ones)? USB-C is rated up to 3A at 5V, even the 'apple charger' wont change that. They just go to higher voltage when delivering more juice which would need a power management IC (PMIC) capbable of this. As far as I know, currently only one SBC largely available can handle higher voltages. So you won't gain much (tbh I don't know if the RPi PSU provideds proper 5+ V at 3 amps - it powers the RPi headless under all my usecases so I'm fine with it - for NAS/mass storage applications I always opted for other SBCs than the RPi)..clicky wrote: ↑Fri Oct 25, 2019 2:24 pmThat seems quite a good idea. Original PSU cannot get two of SSDs powered at the same time and I got an itch to try to rsync one to another and thus kickstart another Pi4 machine (not 100% sure what for, but I have it and why not?!).
Would someone be able to make some post/blog with pictures of how-to? Diagram - which pins (wires) to be cut so such resistor can be added. I have spare Apple adapter for that, one off operation (two SSDs on two USB3 ports on one Pi4). I am happy to source and sacrifice cheap, short USB-C to USB-C cable for operation...
first you limit it to 'only companies request such an information' to build up your case so that the workaround is easy for them. IMO this is likely an issue which affects casual users more (e.g. your RPi sits on the bench and is powered a few ours/day/week etc and you're not willing to have multiple USB-C PSUs on your desk or in a mobile setup). They might want to know when a fixed version might be available.jdb wrote: ↑Thu Oct 24, 2019 7:33 pmWhich, in a roundabout way, validates my original point.
Timeframe/availability information is a necessary input for any company wanting to do volume manufacture.
Now, apply this to the irate requests for "WE NEED A TIMELINE!!!one" - consider a hypothetical company that wants to ship 30000 widgets that have a Pi 4 inside and, for some completely inexplicable reason, have prototyped and tested an arrangement that includes an e-marked cable/supply that *doesn't work* with Pi 4.
Also, consider the fact that the set of power supply assemblies that *don't* work with Pi 4 require extra silicon in the form of a SOP controller chip.
their hypothetical prototype is not broken, your PD implementation is. Cause the fact that the RPi doesn't work in such a configuration came out quite early it's likely that this won't happen anyway. But here's a third option just omit the RPi and opt for a board with a proper USB-C PD implementation or any other sane powering. It's not that there are no other ARM SBCs on the market.
Re: Timeframe for USB C power board revision
LOL. I don't think that's going to work - I'm just optimist that hopes it wouldchwe wrote: ↑Fri Oct 25, 2019 5:59 pmand you think that's gonna change something when you use a 'apple PSU' (it's not only apple, they're just the famous ones)? USB-C is rated up to 3A at 5V, even the 'apple charger' wont change that. They just go to higher voltage when delivering more juice which would need a power management IC (PMIC) capbable of this. As far as I know, currently only one SBC largely available can handle higher voltages. So you won't gain much (tbh I don't know if the RPi PSU provideds proper 5+ V at 3 amps - it powers the RPi headless under all my usecases so I'm fine with it - for NAS/mass storage applications I always opted for other SBCs than the RPi)..


Maybe the right option is just to wire 5V from old PC power supply directly to pins.
Yeah, but, using words my 16 year old would say: "It requires effort" - and also is prone to errors from misinterpretation what I read.drgeoff wrote: Figure it out for yourself. Top left corner of https://www.raspberrypi.org/documentati ... educed.pdf and https://en.wikipedia.org/wiki/USB-C

Thanks - that's first step!jcyr wrote: Here's a schematic. If you're using a premade male to female USB-C cable, only one wire needs to be cut. Cut either CC1 or CC2 and connect the female side to ground through a 5.1 KOhm resistor.
Personally I'd go with the onboard mod pictured above, rather than mangling a perfectly good USB-C cable.

Re: Timeframe for USB C power board revision
Thanks for that reply eham, I appreciate the time you have taken the think about it and respond. The projects I want to do are all personal hobby related so a wait of a few months is no big deal.ehem wrote: ↑Wed Oct 23, 2019 9:46 pmThe official announcement was June 24th. Depending on which dates you consider comparable, 5 months would put revision 2 out in November, while 7 months would put revision 2 in January. This seems reasonably plausible.
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Now glenk, you've got to weigh your options. What is your cost of waiting an additional 1-3 months? Does that cost outweigh the benefit of getting one with a proper USB-C connector? I see distinctly less hassle from not having to worry about non-interchangeable USB-C power supplies, yet as I'm likely to use the official power supply that benefit is distinctly dubious. Meanwhile waiting means delaying the project which I have in mind which has a significant cost.