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Altera_Forum's avatar
Altera_Forum
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12 years ago

QSPI Flash vs SD-Card - HPS flash memory

Dear community,

A quick flash question: Is there any difference between the QSPI Flash and an SD-Card from the perspective of the Cyclone V HPS? (Apart from the obvious ones, the SD-Card being removable and usually bigger).

Does the HPS treat the SD-Card equally to the QSPI Flash or is there any difference? Does the QSPI Flash have any features that the SD-Card does not have?

Because if they are treated equally, why bother having an QSPI flash at all? (Apart from a potentially smaller footprint)

Many thanks,

Claudia

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    RAM -- this is onchip or DDR3 ! Flash is always be ROM :)

    Now SD-card if "loved baby" for Altera and Rockedboards, there full works all worked applications: Linux and RTOSes.

    From QSPI not boot nothing, at least, in capable examples! Although, may be symmetrycal :)

    HPS for embedded application must boot from any flash, which may be soldered on board and visible in address range, or not only defined in BSEL pins for BootROM! Its architectural problems of Altera.

    Insertable ROMs for dependable devices is unprofitable and occupy many volume.

    However, need be other interface to download upgrades (for example, JTAG is small and best and must be always), and SD may re-write on other PC.

    We all want create our board on base SoC CV kit new FPGA+HPS, may be no restrictions and universal HPS boot!
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Hi WitFed!

    --- Quote Start ---

    HPS for embedded application must boot from any flash, which may be soldered on board and visible in address range, or not only defined in BSEL pins for BootROM! Its architectural problems of Altera.

    --- Quote End ---

    What does visible in address range mean?

    --- Quote Start ---

    Insertable ROMs for dependable devices is unprofitable and occupy many volume.

    --- Quote End ---

    Really? SD-Cards are quite cheap. Yeah the footprint on the board is bigger, you are right.

    Many thanks,

    Claudia
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Hi! :)

    QSPI is very-very small in comparison with mechanic insertable cards.

    In devices, ready for users, may be minimum jingles and contacts generally.

    When Altera makes kit, its target was show many possibilityes of many components.

    And so be need BSEL jumpers for show a boot from different sources.

    In typical to-market device is only one boot source, HPS may boot from address 00000000.

    If need be many boots, BSEL may point to many addresses as 10000000, 20000000, ...F0000000 and like this: flash devices always may be readed directly on system bus.

    Then don't need BootROM, Preloader and other complex stadies with 64K-limitation with Release and without sources, big applications may start from flash with interval 1-4-16-128M, init all, include SDRAM, copy self there and run in one stady! Freedom is best, and same freedomical States not love this ! :)