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Altera_Forum's avatar
Altera_Forum
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15 years ago

Configure Cyclone II

Hi !!!

i want to configure a cyclone II in AS mode with a microcontroller which is connected to a SPI flash and cyclone II too. So my question is : When you put nConfig low, every pin of FPGA are they in high Z ??

Thanks in advance

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    During the configuration the I/O pins are set up as inputs with weak pull-up to their respective VCCIO.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    every pin of FPGA are they in high Z

    --- Quote End ---

    Not every pin. If you want to access the AS configuration memory by the processor, you need do deassert nCE.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Thanks for your answer i think it's the solution, but i have an other question about that if i deassert nCE what's the state of the other pin like nConfig, nStatus, ASDO or DCLK ??