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Altera_Forum
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9 years ago

How to tie an output pin to '0' or '1' internally using constraints?

Hi All, How can I define a default (power up) value for the output pin using Quartus-II constraints? I know I can do so in RTL, but I'd like to do it by constraints. The pin should ...
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Altera_Forum
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9 years ago

You can't make a pin drive logic '1' using a constraint. The best you can do is make all unused pins as inputs with weak internal pullups. Internal pullups will keep the pins high as long as they aren't pulled down or driven low externally. Go to Assignments -> Device -> Device and Pin Options -> Unused Pins.