Guest kimiraikkonen Posted September 7, 2007 Posted September 7, 2007 Hello, XP Pro SP2 and have no problems recognizing hubs, but i know / i'm sure as stated in my motherboard's user manual, i have 3 hubs x 2 ports each = total 6 USB ports (USB 2.0) But in device manager it reports 4 USB root hubs and under "power" tab power requirement of device is reported sometimes wrong. For example one day it shows my flash drive requires 200mA to operate, some day it says 100mA is enough. Also at the last root hub(forth one) it says i have 6 ports free (but still usb optical mouse is operating). I'm not quite sure but in device mangager hubs and power requirement report is wrong as i tested. Any comments? Thanks.
Guest R. McCarty Posted September 7, 2007 Posted September 7, 2007 Re: XP's incorrect USB hub report Motherboards have BOTH Enhanced ( USB2 ) and Full Speed ( USB1.1 ) controllers and Root Hubs. There are more USB 1.1 Controllers because USB connections are internally routed. When you plug a USB 2.0 peripheral in the routing connects it to the USB 2.0 Controller/Root Hub. To create an equivalent number of ports ( visualize sockets ) there must be more USB-1.1 controllers and Hubs. These are hard wired to specific sockets. Recent motherboards now provide more than a single Enhanced USB controller. "kimiraikkonen" <kimiraikkonen85@gmail.com> wrote in message news:1189202157.450971.62550@g4g2000hsf.googlegroups.com... > Hello, > XP Pro SP2 and have no problems recognizing hubs, but i know / i'm > sure as stated in my motherboard's user manual, i have 3 hubs x 2 > ports each = total 6 USB ports (USB 2.0) > > But in device manager it reports 4 USB root hubs and under "power" tab > power requirement of device is reported sometimes wrong. For example > one day it shows my flash drive requires 200mA to operate, some day it > says 100mA is enough. Also at the last root hub(forth one) it says i > have 6 ports free (but still usb optical mouse is operating). > > I'm not quite sure but in device mangager hubs and power requirement > report is wrong as i tested. > > Any comments? > > Thanks. >
Guest kimiraikkonen Posted September 7, 2007 Posted September 7, 2007 Re: XP's incorrect USB hub report Yes i have 3 usb 1.1 and a (one) usb 2.0 controller = totally 6 ports. When i plug a usb 2.0 hi-speed device XP does not complain if device is OK, but power requirement decreases sometimes, sometimes increases for the same device. Additionaly, amount of USB ports which are reported under "usb root hub" is frustrating. Could you clarify which number is OK? For example my friend has a 3 year-old notebook with only 2 ports but there are 4 usb root hubs reported under "device manager". Why?
Guest R. McCarty Posted September 7, 2007 Posted September 7, 2007 Re: XP's incorrect USB hub report Never experienced variable mA draws using the same device. On my system the peripherals maintain a constant current. Notebooks have chipsets that can provide more ports than the vendor actually chooses to provide physical ports/sockets. Best tool for examining USB device trees is UVCView: http://www.microsoft.com/whdc/device/stream/vidcap/UVCViewdwn.mspx? "kimiraikkonen" <kimiraikkonen85@gmail.com> wrote in message news:1189203929.918837.169630@r29g2000hsg.googlegroups.com... > Yes i have 3 usb 1.1 and a (one) usb 2.0 controller = totally 6 ports. > > When i plug a usb 2.0 hi-speed device XP does not complain if device > is OK, but power requirement decreases sometimes, sometimes increases > for the same device. > > Additionaly, amount of USB ports which are reported under "usb root > hub" is frustrating. Could you clarify which number is OK? > > For example my friend has a 3 year-old notebook with only 2 ports but > there are 4 usb root hubs reported under "device manager". > > Why? >
Guest RalfG Posted September 8, 2007 Posted September 8, 2007 Re: XP's incorrect USB hub report The number of hubs and ports being reported isn't a problem. They represent the capability of the USB controller chipsets (2x 8 = 16 ports), not the 6 physical USB connectors provided to you on the computer. The specifications in the owners's manual represent what you paid for, not the maximum capability of the USB chipset. Windows reports what the installed USB1/2 chipset capacity (electronic) for connections is, not the physical ports (wiring) that were provided on the computer The USB 2 controller connects to 1 root hub that can operate 8 directly connected ports, although you only have 6 physical ports attached to it. There are 4 USB 1.1 controllers which operate 1 root hub each, with 2 ports each. Again only the same 6 physical ports are connected to the USB 1.1 controllers as the USB 2 controller. Obviously you can increase the number of physical ports by attaching external USB hubs to any of the existing ports. Since the same physical ports are connected to both USB 1.1 and USB 2 controllers the type of USB device that you attach to the port will determine whether that port will connect (electronically) to either a USB 1.1 or USB 2 root hub. Example, an external USB2 hub attached to any of the ports will show up as being attached to the USB2 root hub and controller. A USB 1.1 hub attached to that same port will show up as being connected through a USB 1.1 root hub to one of the USB 1.1 controllers. If you have a memory card reader in the computer it would also be connected through one of those 4 USB 1.1 controllers. "kimiraikkonen" <kimiraikkonen85@gmail.com> wrote in message news:1189203929.918837.169630@r29g2000hsg.googlegroups.com... > Yes i have 3 usb 1.1 and a (one) usb 2.0 controller = totally 6 ports. > > When i plug a usb 2.0 hi-speed device XP does not complain if device > is OK, but power requirement decreases sometimes, sometimes increases > for the same device. > > Additionaly, amount of USB ports which are reported under "usb root > hub" is frustrating. Could you clarify which number is OK? > > For example my friend has a 3 year-old notebook with only 2 ports but > there are 4 usb root hubs reported under "device manager". > > Why? >
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