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Altera_Forum's avatar
Altera_Forum
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15 years ago

QSF setting similar to Xilinx Prohibit

Hello, I would like to know if there is a QSF setting that is similar to the Xilinx Prohibit setting. The prohibit setting disallows the use of a pin location e.g. CONFIG PROHIBIT = "A10";...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

The reserve assignment is what you want to use.

As an example: 

set_location_assignment PIN_P4 -to user_reserve_1
set_instance_assignment -name RESERVE_PIN "AS INPUT TRI-STATED" -to user_reserve_1

What you select for the driving value is up to you and depends on what the pin is connected to. You must have some reason for wanting to prohibit use of it. Do you want to tri-state the pin, give it a weak pull-up, make it drive ground, make it drive high?

Jake