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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...
Altera_Forum's avatar
Altera_Forum
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15 years ago

I made a test for both '0' and '1' at the same time. I had this virtual pin drive a led-blinker, when '0' we have a 2Hz blink, when high a 10 Hz.

When I connected the initialised to '1' virtual pin, the led flashed a 2Hz, steadily.

I then connected the initialised to '0' virtual pin, but inserted an inverter along the way, the led flashed at 10Hz, again steadily.

So I think I am safe to conclude that a virtual in pin of a top level module, the module that ultimately connects the pins, carries a '0' value.

If you look in the Technology Map Viewer in Post-Fitting mode you can find the LUT you mention, but it has a '0' feeding out ...