Generic USB 2.0 hub showing up as USB 1.1
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From: Yousuf Khan on 29 Dec 2007 16:39 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
From: nobody on 30 Dec 2007 02:42 On Sat, 29 Dec 2007 16:39:50 -0500, Yousuf Khan <bbbl67(a)yahoo.com> wrote: >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 Crappy cable? I've seen a few times a 2.0 device gets downgraded to 1.x when connected with a substandard cable. A good quality cable (try Belkin) solved it for me. Oh, one more thought - check where the hub in question was made. If it's China, that explains it. If they deliberately use led paint for children's toys (saves a fraction of a penny per toy vs. non-toxic one), and conveniently forget to put cord into tires (saves both material and labor - a few bucks total per tire - who cares if people die when it blows out), you can expect similar "quality" materials and workmanship from the hub. NNN
From: VanguardLH on 30 Dec 2007 06:20 "Yousuf Khan" <bbbl67(a)yahoo.com> wrote in message news:ipSdnROWzJM6I-vaRVn_vwA(a)giganews.com... >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 Have you visited the manufacturer's web site to get the specs on those USB hubs? Having the same hardware (i.e., chipset) says nothing about how the manufacturer utilized that hardware. Lots of analog modems use the same Conexant chip but the *cards* don't have the same feature set. Same subsystem components do not enforce the same system features. Could be one of the hubs really only is 1.1 compliant and that using it as a 2.0 device is not recommended. Of course, the device could be just a crappy low-grade cheap unit that doesn't properly respond to report itself correctly, or you need a better USB cable. Are both of these a self-powered hub (i.e., they have a power adapter) or a low-power hub that relies on the current supplied from the USB controller at the motherboard? If they are bus-powered hubs, they CANNOT be on the same USB controller. Each controller provides 2 ports (channels) but these 2 ports still share the same controller and so both are limited by a total amperage that can be supplied by the same controller. That's why you see USB ports in pairs but you have to watch how much current is drained by them together. Bus-powered hubs or any other bus-powered devices will tax the low current available from the USB controller, so instead make sure to use self-powered USB hubs, especially considering that you are planning to connect more than just 2 USB devices to the same controller (and possibly not just low-powered USB devices). Initially a USB device is allowed to draw 100 mA but that device may request more power for upstream devices in increments of 2 mA but up to a maximum of 500 mA (and that is across the pair of ports to the same USB controller). For a bus-powered hub, the connected devices may only use a total of 400 mA (100 mA per port) so the hub is limited to 4 ports. If using bus-powered hubs, make sure you are using low-power USB devices (or the high-powered USB device provides its own power supply that is connected to a bus-powered hub). USB devices rated for bus-power draw can be used on a bus-powered hub (but watch the total draw across both USB ports to the same controller). The number of bus-powered or high-power devices that you connect to a self-powered hub depends on how much current that hub can deliver. USB devices are supposed to report their power consumption. Maybe you hubs don't. Or maybe they report too high a consumption to guarantee USB 2.0 mode to work so the controller degrades to USB 1.1 mode. Do you actually have any high-speed USB 2.0 devices connected to the hubs when you boot the OS with the self-powered hubs already powered up? Are they really high-speed USB 2.0 devices (USB 2.0 compliant devices can report as low, full, or high-speed)? For best setup, use self-powered hubs, or connect them to different USB controllers (i.e., they don't share the same port pair coming from the same USB controller).
From: Yousuf Khan on 30 Dec 2007 13:07 nobody(a)nowhere.net wrote: > Crappy cable? I've seen a few times a 2.0 device gets downgraded to > 1.x when connected with a substandard cable. A good quality cable > (try Belkin) solved it for me. Worth a shot, I have tried moving the hub from one port to another, but it made no difference. > Oh, one more thought - check where the hub in question was made. If > it's China, that explains it. If they deliberately use led paint for > children's toys (saves a fraction of a penny per toy vs. non-toxic > one), and conveniently forget to put cord into tires (saves both > material and labor - a few bucks total per tire - who cares if people > die when it blows out), you can expect similar "quality" materials and > workmanship from the hub. Isn't everything made in China these days? Avoiding Chinese made hubs might be like trying to avoid any Swiss chocolate made in Switzerland. Yousuf Khan
From: Yousuf Khan on 30 Dec 2007 13:44
VanguardLH wrote: > Have you visited the manufacturer's web site to get the specs on those > USB hubs? Having the same hardware (i.e., chipset) says nothing about > how the manufacturer utilized that hardware. Lots of analog modems use > the same Conexant chip but the *cards* don't have the same feature set. > Same subsystem components do not enforce the same system features. > Could be one of the hubs really only is 1.1 compliant and that using it > as a 2.0 device is not recommended. Of course, the device could be just > a crappy low-grade cheap unit that doesn't properly respond to report > itself correctly, or you need a better USB cable. Well, as I said previously, these are "generic" hubs, very generic. I doubt any of us have heard of the manufacturers' names: there isn't much point in checking their websites, they probably sell tons of little products. One is from Vantec and the other is Acrox. The Acrox is the older more reliable one. Both of them are advertised as USB 2.0 hubs, and both of them are identified as "USB2.0 Hub" internally, polled from the USB configuration itself. > Are both of these a self-powered hub (i.e., they have a power adapter) > or a low-power hub that relies on the current supplied from the USB > controller at the motherboard? If they are bus-powered hubs, they > CANNOT be on the same USB controller. Each controller provides 2 ports > (channels) but these 2 ports still share the same controller and so both > are limited by a total amperage that can be supplied by the same > controller. Both can be self-powered or bus-powered, they have the power inputs. Only one of them came with an included power cord though. And surprisingly it's the less reliable one that has the power cord. The more reliable one doesn't have one. I have tried that one with and without the power cord, but it made no difference. I have resorted to putting my fast peripherals on the older hub, such an external hard drive, a digital camera, and a Skype phone. They all have their own power cords so they don't need to be powered by the hub anyways. The hard disk and camera show up under the mass storage device class. The slower hub is being used for slow peripherals like mice and keyboards now. > USB devices are supposed to report their power consumption. Maybe you > hubs don't. Or maybe they report too high a consumption to guarantee > USB 2.0 mode to work so the controller degrades to USB 1.1 mode. Both are reporting 100mA. Yousuf Khan |