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Altera_Forum's avatar
Altera_Forum
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13 years ago

DDR SDRAM won't fit!

Hi All,

I am using a cyclone III starter kit, which has the EP3C25F324C6 FPGA on and the zentel A3S56D40ETP-G5 SD-RAM.

I have (i think) added the DDR ram controller in QSYS correctly (I used the information in the system architect design tutorial, which I appreciate s for the NEEK).

I then generated the system and all is OK, no warnings and no errors. I then dropped this into a quartus schematic, connected all the IO to the outputs and bidirectionals. I then did analysis and elaboration which went OK but when I try to compile the project i get some nasty erros the chief of which are:

Error (171000): Can't fit design in device.

I find this hard to believe as there is nothing else in the system to speak of!

also I get:

Error (165024): The DQ group with DQS pin "MEMDQS[1]" has invalid DQ group assignements.

Error (165024): The DQ group with DQS pin "MEMDQS[0]" has invalid DQ group assignements.

I am a little puzzled to say the least.

If someone could shed some light on this for me I would be most grateful.

D

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    When You generate DDR controller, the core also generates a TCL script. Run it.

  • Altera_Forum's avatar
    Altera_Forum
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    Hi Socrates,

    There seem to be quite a lot of TCL scripts generated that are related to the SDRAM, some are in the synthesis/submodules folder and some are in the project folder. Which are you referring to? and what do you mean by run it!

    thanks for taking the time to help.

    D
  • Altera_Forum's avatar
    Altera_Forum
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    Woohoo, it's alive!

    It appears I had two instances of the ALTMEMPHY trying to fit into the FPGA, quite how that happened I don't know but it became apparent when I looked at the TCL file you suggested and saw two lots of differently named tcl scripts. So I rebuilt everything and tried again and it worked. I know have a simple program running from the SDRAM so thank you SOcrates.

    D
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Hi All,

    I am using a cyclone III starter kit, which has the EP3C25F324C6 FPGA on and the zentel A3S56D40ETP-G5 SD-RAM.

    I have (i think) added the DDR ram controller in QSYS correctly (I used the information in the system architect design tutorial, which I appreciate s for the NEEK).

    I then generated the system and all is OK, no warnings and no errors. I then dropped this into a quartus schematic, connected all the IO to the outputs and bidirectionals. I then did analysis and elaboration which went OK but when I try to compile the project i get some nasty erros the chief of which are:

    Error (171000): Can't fit design in device.

    I find this hard to believe as there is nothing else in the system to speak of!

    also I get:

    Error (165024): The DQ group with DQS pin "MEMDQS[1]" has invalid DQ group assignements.

    Error (165024): The DQ group with DQS pin "MEMDQS[0]" has invalid DQ group assignements.

    I am a little puzzled to say the least.

    If someone could shed some light on this for me I would be most grateful.

    D
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    --- Quote Start ---

    When You generate DDR controller, the core also generates a TCL script. Run it.

    --- Quote End ---

    Hi Socrates,

    I have an issue with fitting DDR SDRAM controller on Cyclone III (3C120). I am building a triple-speed Ethernet module using Qsys as per the altera example http://www.altera.com/support/examples/nios2/exm-tse-sgdma.html?gsa_pos=1&wt.oss_r=1&wt.oss=triple

    speed ethernet 13.1

    When I try to build my project in Quartus II, I see the following errors:

    Error (165011): altmemphy pin placement was unsuccessful

    Error (165024): The DQ group with DQS pin "mem_dqs_to_and_from_the_ddr2_bot[0]" has invalid DQ group assignments

    ..

    Error (171000): Can't fit design in device

    Prior to compiling my design, I had run the TCL script, generated by the Qsys. But still, the fitting error persists.

    And, I do not see multiple instance of any design component in my top module. Also, I've a query regarding any modification that is required

    to the TCL script, before I run it?

    Thank you very much.
  • Altera_Forum's avatar
    Altera_Forum
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    I was able to fix this issue by modifying the pin assignments. (ex: mem_dqs_to_and_from_the_ddr2_bot[0] set to SSTL-18 class I (as suggested in the flow messages )) and by back annotating the pin assignments made during the compilation phase.