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Altera_Forum
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14 years ago

Negative slack of Setup found by TimeQuest

Hi everyone, I use "altlvds_tx" (data rate = 300 Mbps, deser factor = 8, tx_coreclock = 37.5 MHz) in my project. Also I have my VHDL module "FSM_Tx_Transport" servicing altlvds_tx. The task o...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Now I'm looking at "Timing Optimization Advisor".

It recommends the use of global clocks.

But Current Global Settings are: Global Signal = Not Set (Recommended: Global Clock).

It's surprise because I suppose the declaration of clocks in .sdc file (I did it with create_clock and derive_pll_clocks commands) makes them global without need of making assignmets in Assignment Editor.

Where is the truth ?

Thank you.