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Altera_Forum's avatar
Altera_Forum
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15 years ago

access epcs from passive serial configuration

Hi. We use ep3c16f484 (cyclone III) with epcs4. In active serial configuration a cyclone is loaded form epcs and can rewrite epcs. But now we want to make board test configuration. In this configuration a cyclone will be configured in passive serial mode and will test epcs. Now we cannot access epcs. The alt_flash_open_dev function returns 0. Can a cycloneIII access a epcs in passive serial mode?

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Did you set the epcs pins as generic i/o in Quartus device configuration settings?

    I think there should be no difference between AS and PS after fgpa configuration has been loaded.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    There is no DCLK in Dual-purpose list, when configuration is passive serial. And Quartus(8.1) forbids to link any output to DCLK.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    So i make active serial configuration and then convert a file to the passive serial rbf. But may be cyclone looks for the msel pins or Quartus makes some changes during converting.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    There is no DCLK in Dual-purpose list, when configuration is passive serial. And Quartus(8.1) forbids to link any output to DCLK.

    --- Quote End ---

    You are right. Probably this is correct since in a PS configuration DCLK is supposed to be driven by an external master, so you should not use it as gpio.

    Anyway, if you are sure the master tristates DCLK after configuration, you can deceive Quartus and possibly connect epcs both to DCLK pin and another i/o pin and use this one for the epcs controller.