Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
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"; disallows the use of pin A10

The only setting I could find is reserve_pin but I am not sure if this does the same as I also have to set a driving value. If this is a similar setting what should I select for the driving value?

Thanks,

Devas

1 Reply

  • 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