I upgraded my computer recently and the new motherboard has USB 3.0 ports throughout, which meant a great improvement in transfer speed for external hard disks.
However I have an ancient Canon flatbed scanner which I use for the occasional document. This was initialised by gscan2pdf, although very slowly, but scans failed with an I/O transfer problem.
Some probing with sane-find-scanner and scanimage, lower level utilities, showed that the scanner wasn't recognised properly, only the driver (plustek) could be ascertained (presumably from the USB vendor and device IDs), but no details about the scanner could be probed.
I remembered a similar situation a while back where a new workstation wouldn't recognise the keyboard and mouse at boot time although later the GUI system did. In that situation, interposing a hub solved the situation. So I put a USB 2.0 hub that I had handy between the motherboard port and the scanner, and lo and behold, everything worked fine from that point.
The specs at the Wikipedia page on USB 3.0 don't clarify whether 3.0 is always backward compatible with 1.1. So if you run into this problem try a hub.
However I have an ancient Canon flatbed scanner which I use for the occasional document. This was initialised by gscan2pdf, although very slowly, but scans failed with an I/O transfer problem.
Some probing with sane-find-scanner and scanimage, lower level utilities, showed that the scanner wasn't recognised properly, only the driver (plustek) could be ascertained (presumably from the USB vendor and device IDs), but no details about the scanner could be probed.
I remembered a similar situation a while back where a new workstation wouldn't recognise the keyboard and mouse at boot time although later the GUI system did. In that situation, interposing a hub solved the situation. So I put a USB 2.0 hub that I had handy between the motherboard port and the scanner, and lo and behold, everything worked fine from that point.
The specs at the Wikipedia page on USB 3.0 don't clarify whether 3.0 is always backward compatible with 1.1. So if you run into this problem try a hub.
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