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Altera_Forum's avatar
Altera_Forum
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17 years ago

cyclone II : dual port dual clock memory possible?

There is any workaround to this problem?

Error: M4K memory block WYSIWYG primitive "vram8k:vram8k_inst|altsyncram:altsyncram_component|altsyncram_3s62:auto_generated|ram_block1a0" utilizes the dual-port dual-clock mode. However, this mode is not supported in Cyclone II device family in this version fo Quartus...

I am using Quartus 7.2SP1 Web edition.

I am implementing a soc, and would like to have 2 ports, dual clock video memory.

Thanks

Roni

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    The error might be related to the M4K issue in the Cyclone II errata sheet. Check the errata sheet to see whether it is OK for your design to use a setting that will let Quartus implement the memory.

  • Altera_Forum's avatar
    Altera_Forum
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    --- Quote Start ---

    There is any workaround to this problem?

    Error: M4K memory block WYSIWYG primitive "vram8k:vram8k_inst|altsyncram:altsyncram_component|altsyncram_3s62:auto_generated|ram_block1a0" utilizes the dual-port dual-clock mode. However, this mode is not supported in Cyclone II device family in this version fo Quartus...

    I am using Quartus 7.2SP1 Web edition.

    I am implementing a soc, and would like to have 2 ports, dual clock video memory.

    Thanks

    Roni

    --- Quote End ---

    I got the same problem, anybody knows how to make it work ? thanks
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    You have to add a default parameter in Analysis & Synthesis Settings, as described in the Cyclone II Errata Sheet (shown as respective tcl command)

    --- Quote Start ---

    set_parameter -name CYCLONEII_SAFE_WRITE "\"RESTRUCTURE\""

    --- Quote End ---

    The memory consumption is however doubled by this workaround. For known fixed devices, another setting exists.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    --- Quote Start ---

    You have to add a default parameter in Analysis & Synthesis Settings, as described in the Cyclone II Errata Sheet (shown as respective tcl command)

    The memory consumption is however doubled by this workaround. For known fixed devices, another setting exists.

    --- Quote End ---

    You're the man. It does work, thanks a lot.