Why do this what I set out to do? Partially for the challenge and fun, partially for the practical needs of keeping that Pi safe, clean and cool - and inside a dust-filtered PC with half a dozen big fans lazily and quietly doing their work seemed a good spot. Planned destiny as part of NUT CI farm could also play a role (but needs stability under stress).
Partially also started from ideas about what to do with the Pi, e.g. making a PiKVM (so it could also be a remote console and power-toggler to that PC) which got ruled out by the stock of extra hardware suggested for that particular job. Jim On Sat, Sep 28, 2024, 19:48 Tim Dawson <[email protected]> wrote: > That, or use a low current source such as the fan header to control a 5v > switch feeding the pi from a different source. Same net result, and no > excess loads on your mobo. (Might be able to work this into the case using > a spare power supply connector to feed it . . .) > > Still have not figured out why though, but that's not relevant to what you > are trying to accomplish. > > > On September 28, 2024 5:57:41 AM EDT, Jim Klimov via Nut-upsuser < > [email protected]> wrote: > >> I guess I should scratch the idea about fan sockets as the power source: >> they are rated typically at 0.2A each, so fan headers should be expected 1A >> max (3A in some vendors/models), well under the 5A that the RPi5 wants. >> >> Jim >> >> >> On Sat, Sep 28, 2024 at 11:52 AM Jim Klimov <[email protected]> >> wrote: >> >>> Follow-up: >>> >>> * Powering the Raspberry Pi5 from an USB-C port wired on the motherboard >>> was much more promising, it survived over 8 hours building NUT in a loop >>> (in a tmpfs). And in the morning I found it turned off (red light on the >>> Pi). >>> >>> * Per >>> https://stackoverflow.com/questions/4702216/controlling-a-usb-power-supply-on-off-with-linux >>> it seems not possible to programmatically truly power-cycle USB port/hub, >>> as 5V pins are "always on"; and per >>> https://stackoverflow.com/a/16316401/4715872 - at least not on MoBo >>> ports (some hubs may have invested into being fully up to spec and control >>> power fully). The referenced uhubctl <https://github.com/mvp/uhubctl> >>> on my PC said "No compatible devices detected!" so I guess that's it. >>> >>> * Whatever I could find with (suggestions welcome) `grep -r . `find >>> /sys/devices/pci0000\:00 -name '*usb*port*'` /sys/bus/usb/devices/` >>> did not expose any differences beside timestamps with the RPi5 plugged and >>> off, unplugged, and plugged back in again (with auto-boot). I hoped for >>> some power draw statistics to at least learn which port it lives on, to try >>> managing that somehow. >>> >>> * Overall, housing the Pi inside a cooled and somewhat dust-protected PC >>> case seems a neat idea, but for powering the Pi, it seems I would need to >>> use a real wall-power adapter (as noted many times on the net, ideally >>> Raspberry's own one as others tend to vary in actual voltage provided under >>> load). >>> >>> * But before that, I'm thinking if I could tap into the ATX power supply >>> though (using "HDD" or "FDD" plugs) or fan sockets (could be individually >>> manageable? gotta exempt one from OS/HW temperature-based mgmt then). >>> >>> Did anyone trod these side paths yet, any learnings? :D >>> >>> Jim >>> >>> >>> >>> >>> >>> >>> >>> On Fri, Sep 27, 2024 at 4:43 PM Jim Klimov <[email protected]> >>> wrote: >>> >>>> FWIW, a few lessons learned: >>>> >>>> * Different USB-A sized ports (even if marked USB-3.2) did not prove a >>>> stable source, with Pi5 occasionally turning off or rebooting. Sort of >>>> behaved well for days, but as soon as I added load like package installs or >>>> NUT builds, it did not survive 5 minutes... >>>> >>>> * Might be the MoBo turning off or cycling the port due to "overload"?.. >>>> >>>> * Tried the `usb_resetter` script (referenced in NUT contribs) and host >>>> `dmesg` did show re-detection of keyboard etc., but a turned-off Pi did not >>>> boot up. Did not check much further, but did harbor hopes that a funny NUT >>>> driver could "shutdown/reboot" the USB port acting as an UPS for Pi... >>>> >>>> * The Pi power socket is dumb-USB so the host does not "see" any IDs >>>> about it. >>>> >>>> * Currently trying with a USB-C port on the MoBo, and a USB-C to USB-C >>>> cable rated for 60W -- and so far it survived a few loops of NUT fightwarn >>>> builds. Complains of undervoltage fairly frequently (every 30-60s), but now >>>> did not crash yet. >>>> >>>> Jim >>>> >>>> >>>> On Mon, Sep 16, 2024, 13:57 Greg Troxel via Nut-upsuser < >>>> [email protected]> wrote: >>>> >>>>> Kelly Byrd <[email protected]> writes: >>>>> >>>>> > With USB-C ports and cables, there are a ton of profiles, I don't >>>>> know what >>>>> > the new Pi's support, but likely something like 3A @ 5V, 9V, or 12V >>>>> over >>>>> > USB-C >>>>> >>>>> Up to the RPI4, I was pretty sure there wasn't PD, just 5V and it drew >>>>> what it drew, and you hoped that the supply was big enough. >>>>> >>>>> It seems the RPI5 will use PD if given a capable supply. Looks like 5V >>>>> 5A, and it won't negotitate higher voltages. There's an official >>>>> supply that does PD >>>>> >>>>> >>>>> https://www.newark.com/raspberry-pi/sc1153/power-supply-usb-c-5-1v-5a-white/dp/82AK3955 >>>>> >>>>> and the output spec is >>>>> >>>>> 5A at 5.1V, 3A at 9V, 2.25A at 12V, 1.8A at 15V >>>>> >>>>> looks like a TUV seal >>>>> >>>>> >>>>> >>>>> I find Jim's way of using this interesting, but my approach is totally >>>>> different. First, when I'm using a Pi, it's because I want a low power >>>>> computer that I can leave on all the time, or can place in a different >>>>> physical location I don't particularly want to do things on a Pi >>>>> instead >>>>> of a desktop. And then I want it to be reliable. >>>>> >>>>> That leads me to plug a power supply into a UPS, or to use POE (from a >>>>> POE switch which is plugged into a UPS). For RPI3, I found a POE >>>>> ejector that splits the POE ethernet cable into ethernet only and a >>>>> micro USB. >>>>> >>>>> >>>>> _______________________________________________ >>>>> Nut-upsuser mailing list >>>>> [email protected] >>>>> https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsuser >>>>> >>>> -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. >
_______________________________________________ Nut-upsuser mailing list [email protected] https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsuser
