If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Generic USB 2.0 hub showing up as USB 1.1
I have two generic 4-port USB hubs that are supposed to be USB 2.0
compliant. The older one is fine, works as advertised. Meanwhile the newer one sometimes shows up under the USB 2.0 root hub (i.e. "Standard Enhanced PCI to USB Host Controller"), or usually it shows up under the slower "Standard OpenHCD USB Host Controller" (USB 1.1). My motherboard (Asus M2NPV-VM) USB ports are all USB 2.0 compliant, and they individually auto-detect whether they need to switch down to USB 1.1 speeds. I'm using a Microsoft tool called UVCView under Windows XP to display the details of the USB devices, including the hubs and roothubs. According to UVCView, the older hub and newer hub seem to have the same chipset vendor (idVendor = "Genesys Logic, Inc."), although externally they look quite different and have different brand names. So I'm not sure why one would be consistently USB 2.0 compliant, while the other one is not. Now another interesting thing I noticed is that the inconsistent hub will only show up as USB 2.0-compliant after I boot into Windows after having previously rebooted from Ubuntu 7.10 Linux (dual-boot system). So maybe Linux does something to the device that puts it right. But when I list the devices while in Linux I see that it is listed under USB 1.1 just like when in Windows. I have no idea why Linux leaves the hub fixed for Windows, but doesn't fix it for itself?! Any idea what's going on with this hub? Yousuf Khan |
Thread Tools | |
Display Modes | |
|
|