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Altera_Forum
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14 years ago

why does ModelSim capture at the same edge

Hi All! Currently I'm seeking for understanding why ModelSim 6.6d is capturing my data partly at the following (as expected) and the same edge of the clock: I'm trying to simulate the behaviour ...
Altera_Forum's avatar
Altera_Forum
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14 years ago

You are probably experiencing simulation 'delta' delays, where the simulator is evaluating several simulation events during zero elapsed time, and the cycle where the rising edge is detected is occurring when not all signals are in their new (or old) state.

You should launch ep_clk slightly before or after the other ep_xx signals to ensure that its simulation cycle is unique, eg., use an after 1 ns delay.

Cheers,

Dave