• Resolved

TUSB8041: Problems detecting downstram devices

Part Number: TUSB8041


We have developed a usb hub board in order to make the interface between 3 video usb devices and a Host PC.

We checked the hub functionalities using a Pen Drive and a USB3.0 Hard Disk. The hub worked as expected.

But when we plug a video device we are not able to identify the video device. Why are these devices not recognized as the other usb3.0 devices?

Could be realted with the configuration of the OTP registers? (We are using the default configuration)

Thanks in advance,

Best regards,


  • Hello,
    Are these video devices working when you connect them directly to the PC?
    What do you mean by "not working"? Are they not being enumerated? Yellow-banged? Enumerated but video is not showing up?...
    Can you share your schematic for review?
    Have you tried with video devices from a different vendor?
  • In reply to Elias Villegas M.:


    I meant they are not enumerated. Yes, I tried with 2 diferent vendors video usb devices.

    I can upload the schematic tomorrow, but the design is based on the tusb8041 dev kit.

    Thanks in advance,

  • In reply to Elias Villegas M.:


    I know its been a while but we continue testing and we realized that the first problem that we were having was a layout issue.

    But know we are having other kind of non-normal behaviour. We are using the TUSB8041 for making stream of 3 video cameras at the same time.

    Two of them have the same name, could be a problem when connecting 2 devices with the same name?
    We are not having problems when conecting 3 cameras that enumerates with different names but in the system we have 2 cameras with the same device ID. Could be this an issue?

    Best Regards,

  • Genius 15090 points

    In reply to Juan Jose Frutos Andreu:

    Hello Juan,

    The host driver may have an issue with two devices with the same name.  Do the cameras have individual UUIDs or Serial Numbers, or are they the same?  The hub only routes packets to/from the host it doesn't "look" at the data.

  • In reply to JMMN:


    We just find out that the issue is related with the timimg of some initial parameters that the host must send to the cameras.

    We had increase the timing between packets and it works fine now.

    Just for your information with comertial hubs we can achieve the transactions of this packets quiker.

    Thanks for the support given.