Personal computers have limited USB resources. Even though a single USB controller *theoretically* can support up to 127 USB devices, in practice this depends on how the computer's USB system is implemented, the nature of your USB peripherals (e.g., hub vs. mouse), and and how you attach your USB peripherals (not all USB ports are created equal). In brief, USB peripherals connected to your computer form a tree, starting with the root hub(s) within your computer. This tree can, at most, be 7 layers deep. If you encounter an issue and your computer claims that it is out of USB resources, the most likely scenario is that the USB tree depth is too deep. Depending on how your computer was designed, the USB ports on your computer may already be two or more levels down in this tree, compounding the problem. See this web page for more detailed information about USB topology: http://www.usblyzer.com/usb-topology.htm.
Different operating systems have different tools available for viewing your systems current USB layout, including any connected peripherals:
- OSX: The built-in system information tool available on clicking on the Apple icon -> "About this Mac" -> "System Report" -> USB
- Windows: USB Device Tree Viewer (http://www.uwe-sieber.de/usbtreeview_e.html)
- Linux: There is a USBView package available for most distributions
A 6-dock docking station requires three levels of the USB depth for all of the docks to work. In general, it is recommended that your docking station is plugged directly into one of the USB ports on your computer and not a USB hub, in order to minimize the overall USB tree depth. If you have to use a USB hub to connect all of your peripherals, we recommend that you use a 4-port external hub instead of a 7-port hub, as 7-port hubs introduce two levels in the USB topology, while a 4-port hub only introduces 1 level. Access points only require 1 level of the USB tree depth.
Here is a general approach for connecting your USB peripherals. This assumes that you have at least 2 USB ports on your computer.
- Start without any USB peripherals connected to your computer (unless you need a mouse for navigation)
- Take all sensors out of your docking station and plug the docking station into one of the USB ports in your computer. Confirm that all of the LEDs turn green, indicating that they have been correctly detected (enumerated) by your computer. Also confirm that you do not receive any error messages from your computer's operation system. If not all docks enumerate correctly, try the other USB port on your computer.
- Plug the access point into an open USB port. Confirm that the LED turns green, indicating that it has been correctly enumerated.
- Use your remaining USB ports (if you have any) for other USB peripherals. If you only have 2 ports and you have more USB peripherals to attach, plug a 4-port hub into the 2nd port, and plug your access point and other peripherals into this hub, leaving the docking station plugged directly into your computer.
- Confirm that your hardware works by configuring the system for recording.
Another issue that we have encountered has to do with the USB 3.0 driver on your computer. We have seen this on some Dell's and Lenovo's in the past, and it may affect other computers using the Intel USB 3.0 eXtensible Host Controller Driver. In some cases, machines that used to work now don't because a subsequent USB driver update by the PC manufacturer and/or Microsoft has caused this issue. Here is one Microsoft forum topic that discusses this, including the USB tree view with and without the USB 3.0 eXtensible Host Controller drivers installed (when installed, all devices end up on the USB 3.0 bus, which appears to be problematic for many people):
While investigating the solution for this, a couple of suggestions have been made:
- Uninstall the USB 3.0 driver by clicking "Uninstall/Remove program" in Control Panel. This will disable support for USB 3.0 devices. None of our devices require USB 3.0, but make sure that you don't have other USB peripherals that do.
- Disable the USB 3.0 port in your computer's BIOS settings at startup. This is machine dependent, so you will have to check your PC's documentation on how to do this.
- Update the USB 3.0 driver either through your PC manufacturer's updates or by visiting Intel's web page (http://www.intel.com/content/www/us/en/support/detect.html)
We have encountered cases where each one of these options have worked, but have also encountered situations where none of them do. There is simply too much variability in USB chipsets and drivers on the market to have a blanket solution for each scenario.