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Altera_Forum's avatar
Altera_Forum
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11 years ago

Send data over USB from Arrow SoCKit

In the past I've used https://github.com/mzakharo/usb-de2-fpga to send data from a DE2 to a PC over USB (mzakharo, if you ever read this, thanks for all the effort put in writing it!).

How would I do the same (send data from board to PC) with an Arrow SoCKit? Is an implementation available from Altera or is there a similiar project as mzakharo's for the SoCKit?

Preferably using only the FPGA side of the board.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    The SoCKit runs Linux, and I think the kit has USB OTG, so you should be able to configure the Linux gadget device interface to make your SoCKit appear as a USB device of some sort.

    Someone else asked a similar question a while back ...

    http://www.alteraforum.com/forum/showthread.php?t=46490

    perhaps that person got it working.

    If you do get something working, please post your results.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    That would require using the HPS part of the device.

    Can the USB be used with the FPGA-side only?
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    --- Quote Start ---

    That would require using the HPS part of the device.

    Can the USB be used with the FPGA-side only?

    --- Quote End ---

    Look at the block diagram on the second page of the schematic; there is no FPGA I/O connection to an external USB PHY like there is on the DE-series boards. The ULPI PHY connects to the HPS side.

    I'm sure there is probably some option for the FPGA to access the HPS peripherals and you could use that to access the ULPI PHY, but that approach is probably a waste of your time. Software already exists for interfacing to the ULPI PHY, so its likely a more productive application of your time to use the HPS-to-FPGA bridges to transfer data to the HPS side and then use the processor to pass that over USB.

    That's just my opinion of course :)

    Note: there might be a way of customizing the USB DMA buffers so that you can transfer from FPGA-to-USB, but you would use Linux on the processor to implement/coordinate that.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    I agree with what Dave said since having to move the USB software stack into the FPGA in order for it to have control over the HPS USB controller would be a lot of work. I suspect the USB device on the DE2 board provided a simple interface not requiring a USB stack to move data back and forth so that's why it was feasible to connect the USB device directly to the FPGA.

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    So far I haven't used the HPS side of the board. The HPS part is outside of the scope of my current project.

    I guess I just got the wrong board for my current project, again. Thanks for helping out guys, at least I know now it's not worth the effort to continue this path.