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Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

how to fix this warning.

I got warning message from Quartus, don't know what its mean, the code works fine. just want to understand it.

thanks

Warning: At least one of the filters had some problems and could not be matched

Warning: *ws_dgrp|dffpipe_se9:dffpipe18|dffe19a* could not be matched with a clock or keeper or register or port or pin or cell or partition

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    The warning you are getting is from an invalid Timing Constraint. Most likely it comes from an "SDC" file created by some piece of Altera IP that you are using. It's probably not a problem. Many times, Altera's SDC scripts are so generic that they commonly make constraints on portions of the design that may not necessarily exist in your particular configuration.

    Jake
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    correct.

    could it be that you use an ip where one output is not connected or an input is connected to vcc or gnd. in that case it could be that the synthese removes this pin but one of the sdc files has a contrain for it. due to the removement by the synthese this sdc constraine can not be matched.