Hmmm… I re-did my experiments just to be sure, and It turns out to be more complicated than I originally thought.
It appears that the manufacturer/brand of USB flash memory stick plays an important role in what happens. I’ve got three different USB sticks (all nominally USB3) each with a different pattern of behavior. One, 16GB manufactured by Samsung, works no matter where I plug it in or whether or not I use a hub. One, 16GB manufactured by Kensington — brand name “DataTraveler”, Has pretty much the behavior I originally described, but occasionally flakes out and just doesn’t work at all — then when I power-cycle the Turbot it works again. And the third one, 16GB manufactured by ADATA, behaves as I originally described, and does so reliably. All of the sticks work reliably when plugged into the USB3 slot on the Turbot when the OS is Debian Linux, but are as described (flakey in various ways) when the OS is UEFI firmware. Curiouser and curiouser! Rick On Jun 9, 2018, at 2:24 AM, Rick Thomas <rbtho...@pobox.com> wrote: > I have downloaded and copied a debian install .iso to a USB3 memory stick. > When I plug the stick into the USB3 (lower) slot on my MinnowBoard Turbot and > try to boot from the stick the UEFI Boot Manager doesn’t see it. > > However, > > 1) If I plug the very same stick into the USB2 (upper) slot, then the UEFI > Boot Manager does see it and will boot from it. > > 2) If I plug the very same stick into a USB2 hub which is plugged into the > USB3 (lower) slot on the Turbot, then the UEFI Boot Manager does see it and > will boot from it. > > 3) If I copy the .iso to a USB2 memory stick, the UEFI Boot Manager will see > it and boot from it regardless of which slot it is connected to. > > “Not the sort of behavior you ordinarily expect from a major appliance.” > — Ghostbusters > > Anybody got a clue? > Thanks! > Rick > > _______________________________________________ elinux-MinnowBoard mailing list elinux-MinnowBoard@lists.elinux.org http://lists.elinux.org/mailman/listinfo/elinux-minnowboard