BF706 Hibernate, Wake on USB

Dears:

       Here are two questions :

1、After I use active Hibernate, I find that USB is not found in my device manager? I don't think he can't recognize it, because I can't seem to wake up.

2、Whether USB wake-up can be realized by sending command to the host or other ways? Although the principle is through D -, D + detection, but how to achieve the means in the application.

THANKS!

  • +1
    •  Analog Employees 
    on May 22, 2020 9:38 AM 6 months ago

    Hello ,

    As mentioned in the HRM, are you taking care of below points.

    A USB event (active high polarity only) can take the processor out of Hibernate. To retain the USB communication after exiting deep sleep, the PHY must be configured appropriately to retain the state of D+/D-, thus avoiding the need to re-enumerate. The following condition must be satisfied from the USB PHY. Before entering deep sleep, the USB_PHY_CTL.HIBER bit is set (= 1) and the USB_PHY_CTL.RESTORE bit is cleared (= 0) in the PHY control register. This operation is usually done in the USB suspend handler.

    For more information please refer the Wake up from Hibernate section in the HRM (PageNo:251/2223) of ADSP-BF70x. You can find the HRM from below link,
    www.analog.com/.../BF70x_BlackfinProcessorHardwareReference.pdf

    Regards,
    Anand Selvaraj.