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Altera_Forum
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13 years ago

State A => State B multicycle path?

Is there a way to tell TimeQuest that all signals launched by State A and captured by State B are part of a multi-cycle path? My combinational path delay is too large so i'm adding a timer to delay m...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The time a FF takes to resolve from meta-stability is not constant. Even for a modern device, there's a tiny but non-zero probability that it's long.

But anyway, the problem is that you're saying one thing and writing code for another.

set_multicycle_path -setup -end -from [Launch_FF] -to [Latch_FF] 2

set_multicycle_path -hold -end -from [Launch_FF] -to [Latch_FF] 1

^^ This should be used when the output of Launch_FF is not used by Latch_FF until 2 clocks later.

On the other hand, you keep writing about the output of Latch_FF not being used for until 2 clocks later...

You need to be sure about what you're constraining.