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sof event

Sank P

I am programming an lpc2148 to read signals from the pc via usb in isochronous mode. I want to set a bit in order to bring about start of frame event. Whcich bit in which register?

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    > I want to set a bit in order to bring about start of frame event. Whcich bit in which register?

    FRAME bit on USBDevIntEn register enables SOF interrupt, USBDevIntSet generates the interrupt for test, USBDevIntClr clears the flag.

    SOF reception on the device may drop.
    As the USB engine on LPC family doesn't have hardware SOF recovery (*1), a digital PLL (a timer) on the firmware tracks FRAME (SOF) interrupt interval.
    isoc transfer is handled using this recovered SOF timing.

    (*1) SiLabs 'F32x/34x and EZ-USB equips hardware SOF recovery.

    Tsuneo

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  • 0

    > I want to set a bit in order to bring about start of frame event. Whcich bit in which register?

    FRAME bit on USBDevIntEn register enables SOF interrupt, USBDevIntSet generates the interrupt for test, USBDevIntClr clears the flag.

    SOF reception on the device may drop.
    As the USB engine on LPC family doesn't have hardware SOF recovery (*1), a digital PLL (a timer) on the firmware tracks FRAME (SOF) interrupt interval.
    isoc transfer is handled using this recovered SOF timing.

    (*1) SiLabs 'F32x/34x and EZ-USB equips hardware SOF recovery.

    Tsuneo

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