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Altera_Forum
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17 years ago

Problems with pin assignments with Cyclone III starter board

Hello,

I have been attempting to program my FPGA to communicate with the SSRAM provided with the cyclone 3 starter board. However, when I attempt to assign pins H3 (FLASH_SRAM_DQ0) and D1 (FLASH_SRAM_DQ1) to my design I encounter errors in the fitter portion of the compilation. (Error: Can't place pins assigned to pin location Pin_D1 (IOPAD_X0_Y27_N7) and Error: Can't place pins assigned to pin location Pin_H3 (IOPAD_X0_Y22_N7)). Why do these errors occur, there does not seem to be any errors with any other pin assignments. Thanks.

Andre

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    The said pins are pins used by the AS configuration interface, apparently you enabled AS configuration and reserved the pins. AS configuration isn't used by the starter board.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Thank you for your help. However, as I have a mediocre understanding of Altera FPGA programming and the Quartus II software I have no idea how to change this setting. Could you give me a few more details please, or at least tell me what AS stands for? Thanks.

    Andre
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    AS means active serial configuration, the starter board actually uses AP (active parallel) configuration, but it don't need to be set explicitely in Quartus.

    Assignments->Device->Device and Pin Options is the place for configuration settings. The important thing is that you set the Dual-Purpose Pins to regular i/o. The configuration scheme should be better set to passive serial to avoid conflicts with IO voltage.
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Thanks again, but I appear to continue encountering the same problem despite these changes. I have tried changing the configuration to passive serial as suggested and had the very same errors. When I attempted to change the configuration to active parallel I got these errors for multiple pins including the two problem pins. Is there something else that i am missing? Thanks.

    Andre
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Thanks, that seems to have done the trick, I guess I missed that extra detail..

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    I have the same problem and I tried this method, and it works!! Thanks!:)