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amildm's avatar
amildm
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4 years ago
Solved

seed -> how to get same SOF for each compilation run?

Hi All, Each time when I compile the design, I'm getting the different SOF files even I don't change anything neither in my Design nor in QSF... the resulting SOF will be different... Sho...
  • ak6dn's avatar
    ak6dn
    4 years ago

    The source files drive the logic generation / mapping phases.

    So if you compile with the exact same sources, the logic produced will be exactly the same.

    The SEED value only drives the fitter.

    Different SEED values will produce different placements of the exact same logic.

    So if you don't change the source files, the logic will be the same.

    If you don't change the seed, the placement will be the same.

amildm's avatar
amildm
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4 years ago

thanks for the valuable info!

How can I know the seed, which was used for the each compilation?

If I'll set the SEED as you mentioned

set_global_assignment -name SEED 42

and will not change neither RTL nor QSF (constraints), will I be guaranteed that the final Netlist, Route and Timing be same after each project compilation (with the same SEED)?

How can I read the SOF/JIC timestamps using the System Console?