"Steven M. Bellovin" <smb@cs.columbia.edu> writes:

> I know that it's currently not possible to plug a USB 1.1 device into a 
> 2.0 hub connected to a 2.0 port.  I have no idea why this should be; 
> I'll just assume that's some side-effect of weirdness in the USB spec.

USB 2 hubs are more complicated beasts, and we don't have code to
program their transaction translators that take high-speed data from
the host and feed it as full or low speed data to the devices (The
description of how this works is fully 10% of the USB 2 spec).

> However...  If I were to plug a 1.1 hub into the machine's 2.0 ports, 
> and then plug a 1.1 device into that hub, would it work?

Yes. The controller will hand off that port to the USB 1 companion
controller, and it'll all be a USB 1 universe.

        - Nathan