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AAbro1's avatar
AAbro1
Icon for New Contributor rankNew Contributor
6 years ago

I have a basic question about Quartus tcl command "get_fanins". so I noticed that there are many options for this command and I'm confused which option should I use?

I'd like understand the difference between these 3 option:

get_fanins -async

get_fanins -sync

get_fanins -clock

because in the "get_fanin -help" I didn't understand the difference.

is there any exemple that can show the difference between these options?

4 Replies

  • KennyT_altera's avatar
    KennyT_altera
    Icon for Super Contributor rankSuper Contributor

    What u can do is use the tecnology map viewer to look into the netlist.

    -asynch Traverse through asynch edges, this normal happened on after LUT1 where no clock involve.

    -synch Traverse through synch edges, usually, on the register where clock is involve.

    -clock Traverse through clock edges, on the clock path rather than the data path. for example, output of PLL.

  • AAbro1's avatar
    AAbro1
    Icon for New Contributor rankNew Contributor

    The definitions are not clear

    -asynch Traverse through asynch edges

    -clock Traverse through clock edges

    -synch Traverse through synch edges

    So for example I created this test case:

    I get the fanins of the "In_pin" input using "-async" , "-sync" and "-clock" option and I get no difference between the 3 results.

    So how can I see the difference between these options in a design?