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Altera_Forum's avatar
Altera_Forum
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18 years ago

initializing M-RAM

Q's MegaWiz does not let me setup a MIF or a HEX for a M-RAM.

I would like to let this device come up with a predifined pattern in the RAMs. (never changes).

Ist there a way to do this though? - over the way of the system content editor ?

... via JTAG ?

I need a way for operational mode not only during development process ...

The only idea I currently have, is to use aother small RAM, load it with a ZIP file and unpack the data while setup phase. (a strange idea, of course :D )

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    --- Quote Start ---

    Q's MegaWiz does not let me setup a MIF or a HEX for a M-RAM.

    --- Quote End ---

    The M-RAM itself does not support memory initialization during configuration. This is documented in the device handbook.
  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    I get the same problem. Can you try this way:

    use an extern eeprom, say 24c32, depending on your size. store your data in the eeprom.

    implemente a I2C interface and related read logic in your fpga.

    whenever your fpga reset, it can read data from eeprom and init your ram.

    You may need a init_done signal to let other logic know when to start their operation.
  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    This would require a new (modified) hardware which I cannot create. Anyway there is the opportunity to do this configuration from an external PC over PCI. :cool:

    It would have been just fine to have it ready configured in the data stream.:rolleyes:
  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    Use M4K blocks to initialize data. You can go up to 256 KB in a stratix 2 (180) fpga.

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    --- Quote Start ---

    This would require a new (modified) hardware which I cannot create. Anyway, there is the opportunity to do this configuration from an external PC over PCI. :cool:

    It would have been just fine to have it already configured in the data stream.:rolleyes:

    --- Quote End ---

    Yes, this will be your best approach.

    It's all in the details.

    Good luck,

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