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TMS320F28388S: Is There an Unobtrusive USB Data Read Register

Ed Sanders
Genius 4305 points

Part Number: TMS320F28388S

Greetings,

 

                In the SPI, there is an address, SPIRXEMU, which can be read to see the received data without affecting any of the flag and status bits.  Is there an equivalent for the USBFIFOx registers?

 

Thank you,

 

Ed

  • +1
    TI__Mastermind 37465 points

    Ed

    The USB peripheral does not provide a non-destructive (emulation/peek) read path for its FIFO data. Here's the key distinction:

    • SPI (SPIRXEMU): Reading SPIRXEMU returns the same received data as SPIRXBUF but does not clear the SPI INT FLAG (SPISTS.6). This allows a debugger to inspect data without disturbing normal operation 1.

    • USB (USBFIFOx): Reading the EPDATA field of USBFIFO0, USBFIFO2, USBFIFO3, etc., unloads data from the Receive FIFO — the read is destructive. There is no shadow or EMU-equivalent register documented anywhere in the USB register map

  • 0 in reply to Siddharth Deshpande
    Genius 4305 points

    That is what I thought.  I was hoping I was wrong.  Thank you for checking.

    Ed