Unable to Connect More Devices — USB Endpoint Limits

If you’re unable to connect more devices to your hub, or if already-connected devices are starting to display unusual behaviour, you may have reached the Endpoint limit of your USB controller. This can prevent you from attaching additional devices to your host system.

Endpoint Memory vs. Endpoint Limit

In some cases, the issue may be that you have run out of Endpoint Memory, not necessarily hit the Endpoint limit. If this is the case, consider switching some devices to USB 2. USB 2 connections use half the Endpoint memory of USB 3, allowing more devices to be connected.

Note: Switching to USB 2 will limit your charging and data transfer speeds.

Changing USB Connections to USB 2

You can force all USB connections to use USB 2 by disabling USB 3 in the BIOS during start-up. Alternatively, a simpler method is to use USB 2 cables for those specific connections.

For more detailed information on Endpoint limitations, refer to our article on Endpoint Limitations.

How to Check Device Endpoints and Endpoint Memory

To check the number of Endpoints or the amount of Endpoint memory being used by a device:

1. Open either LiveViewer or Cambrionix Connect.
2. Click on ‘Hubs’ in the menu bar.
3. Select the hub that has the device you want to check.
4. Click on the device in question.
5. Within the device information, you should see a section for ‘Endpoints’ displaying all relevant information for that device.