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Altera_Forum's avatar
Altera_Forum
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12 years ago

User data in CFI flash via MAX2

Hi,

I am having troubles understanding how I could use the CFI flash for user data on this stratix iv gt board (http://www.hitechglobal.com/boards/stratix4gx.htm). My problem stays in the fact that the CFI flash shares no pins with the FPGA, as in the attached images.

Is there any IP that I could use to read/write to the cfi flash from a NiosII? I don't seem to have any GPIOs to interface the MAX 2 and use the MAX 2's PFL core directly...

I appreciate any help!

Thanks!

https://www.alteraforum.com/forum/attachment.php?attachmentid=7839 https://www.alteraforum.com/forum/attachment.php?attachmentid=7840

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    Is this a custom Stratix IV GT board, or an Altera Development Kit?

    Conceptually the MAX II configuration could be designed to operate in FPP mode at power-on, and then switch over to a bridge mode, where it provided access to the Flash via the Stratix IV GT FPP data bus. Unfortunately there are only 8-bits on that bus, so you'd have to come up with a protocol for the 8-bits to indicate read-to-flash and write-to-flash. This is not that difficult, in that examples of this type of protocol already exist, eg., see the JTAG-to-Avalon-ST bridge protocol

    http://www.ovro.caltech.edu/~dwh/correlator/pdf/altera_jtag_to_avalon_analysis.pdf

    Unfortunately this bridge logic does not "come for free", so if your MAX II is already 100% used with a PFL configuration controller, there won't be any space for your bridge logic :(

    If you have a schematic for the board, I can take a look, and could provide other suggestions.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    Thanks for the answer, that's what I feared. The development board is not from Altera, but from HiTechGlobal.

    I have attached the schematic page concerning CPLD/CFI.

    Thanks for the help!
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    The development board is not from Altera, but from HiTechGlobal.

    I have attached the schematic page concerning CPLD/CFI.

    --- Quote End ---

    If you are happy to reproduce the MAX II configuration controller, then you can do whatever you like with this board. If HiTech will provide you with the MAX II .pof image, then you could always program the original image back into the CPLD.

    The MAX 570 CPLD is not very large though, you'd have to code up a custom FPP controller, and then your bridge, and see if the logic fits in the MAX II.

    Cheers,

    Dave