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Altera_Forum
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17 years ago

help: One fitter problem

hi, when i configure my board,there is always one mistake tips " Error: Selected device has 52 RAM location(s) of type M4K RAM. however,the current design needs more than 52 to successfully fit." in the step of Fitter.

My FPGA IS ep2c20f484c7 and, this problem rise during adding customer board. I assigned the pins follows the altera references document and it can Analysis & Synthesis successful, but can't Fitter.

how should i do to Fitter successful?

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    I dont know what you are trying to do but this error message certainly says that memory block(s) you have instantiated in your design exceeds internal memory available in to current FPGA device. So you should try reducing use of internal memories.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    How did you insert the RAM in your FPGA? Using a MegaFunction or using VHDL/Verilog code?

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    The RAM blocks can be utilized only according to the available block configuration. Thus there may be a discprepancy between design RAM usage and occupied blocks. Furthermore, with Cyclone II, the block count is doubled for some configurations due to the CYCLONEII_SAFE_WRITE parameter. See Cyclone II erata sheet for details.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    thanks for all your suggestions. I'm sorry for these days i have been watching Olympic games and didn't notice your replies timely.

    hi,OrchestraDirector,i insert my RAM in the SOPC through the tag on-chip memory with 4Kbytes. I think is enough but i don't kown why it's come out such a error.

    hi,FvM, thank you for your advice. i'll check my RAM assignment with the erata sheet in details.