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Altera_Forum's avatar
Altera_Forum
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14 years ago

Explicitly leave pins unassigned in Quartus?

There are pins in the ports of my top level entity that I do not want assigned to any pin, but I don't want the fitter auto-assigning them for me. Is there a way to designate a port as "do not assign" - my top level entity is something that is used to varying degrees in several different designs, and in some designs more of the ports are used than others. Any thoughts here?

-R

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    One way is to use a wrapper that has only the ports that you require and bury others inside. I assume you mean outputs which can be left open. For inputs you may run into trouble if undriven.

    There is also the setting of virtual pin but I am not sure if it is good for your purpose.
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    You can set them as virtual in the assignment editor and you no-long map to an io port