On 09/23/11 07:27, Alan Stern wrote: > On Thu, 22 Sep 2011, Iain Barker wrote: > >> Hi all, >> >> Is it possible to limit the maximum speed at which a USB 2.0 HUB will connect to USB devices? >> e.g. to make USB 2 devices connect at FULL_SPEED instead of HIGH_SPEED > > The only way to do this is to force the hub itself to connect at full > speed. There's no way to tell a hub to degrade just one of its ports. > If the hub is plugged directly into an EHCI controller and there's no > companion USB-1.1 controller (as is the case with Intel's > "rate-matching" hubs), there's no way to do it at all. > Hi Iain and Alan, Yes, there is a way to do it. Connect a FS only hub in front of the one you want to downshift. That will shift the entire downstream bus to FS only. A FS hub may be hard to buy right now, but if you have been doing usb for several years you may have one in a junk drawer. FS hubs may be referred to as a USB 1.1 hub. Regards, Steve -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
