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 >> >
_______________________________________________ Nut-upsuser mailing list [email protected] https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsuser
