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Altera_Forum's avatar
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

1) I think it's propagation delay. And you can move on wirth your design.

2) You should never design without a reset value and never simulate without applying a reset for a sufficnet long period of time.

3) The initial value, to the best of my knowledge, is not sythesized and only creates discrepancies between RTL and gate level simulations.

4) Never assume that somthing has a given value 'at startup'. It's your reset that fix the design to a known state