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USB low-full-high speed peripherals Forum Discussions

Not applicable

 hi, Sir/ Madam


 now I want to use the GPIF to collect data from an ADC.  every convertion will product 6 words of data. These data will be write into the FIFO(e.g. using the EP2). I know the FIFO pointer will increase after the data bus on "Activate". 


but I have to give a time stamp before the 6 words  be writed into the FIFO. I want to use EPxFIFOBUF to accomplish this goal.


however, I am afraid the GPIF will overlap the time stamp. 


If I  use the EPxFIFOBUF, like 


EPxFIFOBUF[3] =12;


EPxFIFOBUF[4] = 14;


atfer this opration, will the FIFO pointer point to the EPxFIFOBUF[5], or the FIFO pointer won't have any different?


by the way, can I use the FIFO pointer directly in the 8051? Like what the GPIF do.


thanks a lot!





1 Reply
Not applicable

Accessing the buffer while using GPIF has to do with the mode of operation you're in (auto mode or manual mode). Even in that case you won't be able to play with the buffer in the way you're suggesting. GPIF will start writing from location 0.
What is the transfer speed you're looking at?
Go through the GPIF chapter for more details