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Altera_Forum's avatar
Altera_Forum
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9 years ago

Cyclone V spi memory access

Hi,

I wanted to know if the spi flash memory which is present inside the cyclone v can be accessed directly by an external flash. If so can anyone guide me through to how to do it as I am not able to since all the flash pins are being tied to the fpga.

Thanks,

Sid

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    9 years ago

    --- Quote Start ---

    If you want to be able to access the quad SPI flash that is used to configure the image for the FPGA after the configuration is complete, you can instantiate the alt serial flash module that will allow you to access the FPGA pins connected to the SPI device. I use this block to allow my SPI flash config memory to be accessible via the JTAG chain, but it has capabilities beyond just this function.

    All the details are here: https://www.altera.com/literature/an/an370.pdf

    (https://www.altera.com/literature/an/an370.pdf)

    You want to look at the 'Share ASMI interface in your design' option description.

    --- Quote End ---

    I did get access to the flash. Thanks for the info and the document. :)
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    There is no SPI flash memory that is internal to a Cyclone V device.

    Are you referring to the SPI master / slave controllers in the HPS Cyclone V SE devices?

    What specific Cyclone V device are you working with?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    --- Quote Start ---

    There is no SPI flash memory that is internal to a Cyclone V device.

    Are you referring to the SPI master / slave controllers in the HPS Cyclone V SE devices?

    What specific Cyclone V device are you working with?

    --- Quote End ---

    I am referring to the quad SPI flash which is external to the Cyclone V.

    I am using the device CycloneV : 5CEFA4U19C7

    The flash signals are tied to the FPGA and I am not able to use those pins as a normal IO. I want a method or a way to access those pins directly.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    If you want to be able to access the quad SPI flash that is used to configure the image for the FPGA after the configuration is complete, you can instantiate the alt serial flash module that will allow you to access the FPGA pins connected to the SPI device. I use this block to allow my SPI flash config memory to be accessible via the JTAG chain, but it has capabilities beyond just this function.

    All the details are here: https://www.altera.com/literature/an/an370.pdf

    (https://www.altera.com/literature/an/an370.pdf)

    You want to look at the 'Share ASMI interface in your design' option description.