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Altera_Forum
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15 years ago

Toplevel Simulation Control Signal And Retain Post-Fit Netlist

I am working on a large CycloneIII design using QuartusII v9.0. In our design we have a toplevel input simulation control signal that is routed to various aspects of the design. This simulation...
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Altera_Forum
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15 years ago

Thanks josyb.

I understand what a virtual pin is for but what I would like to determine is what QuartusII internally assigns the virtual pin node too. The help says it uses a LUT for a virtual pin so does this mean it is assigned VCC, GND or left floating? Is the LUT value deterministic?

Your test results are interesting as it suggests it is assigned to GND but I don't think we could conclude that because a floating node can still produce this outcome.

I am not sure where to go with this one.