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USB Hub controller

sagar salunkhe

Hi,

I am using a TM4c123 series controllers with 1 USB host port. Now I am using the same port using the a USB switch to use the keyboard and pendrive. But i want to use them both without switching. I guess this is possible if a USB HUB controller with 2 or 3 downstream ports is available. So how should go about it, are there any controllers which such capabilities available.

Regards

Sanket

  • 0

    TM4C123 has a silicon bug, which disturbs hub operation with low-speed device.
    www.ti.com/.../spmz849c.pdf
    "USB#01: USB Host Controller may not be Used to Communicate With a Low-Speed Device When Connected Through a hub"

    Wait until they would release fixed silicon.

    Tsuneo

  • 0 in reply to Chinzei Tsuneo

    Hi,

    I am newbie to USB protocol.I have read about basic working of USB, how it works, descriptors,
    endpoints and other related things.
    I have now taken a sample code for understanding how USB works. I am using the stellaries USB stack and the MSC example.
    In the stack there is a interrupt handler USB0HostIntHandler which is called continuously which in turn calls other handlers according to ulStatus.
    According to my reading USB is a polling mechanism.I am not understanding how the above mentioned handler is called continuously, even if there is no change on D+ and D- lines.
    This is really important for me to understand as it seems everything starts from here in the USB stack.

    Regards
    Rajat