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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 configurat...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

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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.