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Altera_Forum
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15 years ago

ModelSim undefined initial value

Hello, I am trying to do some simple simulation using modelsim-altera and am seeing undefined value for output "result" and it stays like that until 10ns or so into the simulation. Here is the examp...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I think you are complicating yourself too much. Once again, forget about gate-level/timing simulation.

The output should not be undefined. It is probably an artifact of non-accurate gate-level simulation, combined with non-recommended testbench practices. In particular, avoid using a zero delay, just don't use any delay at all in that case, and use non-blocking assignments.

But yet once again, I'd avoid gate-level simulation altogether.