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  1. #1
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    How to apply set_property ALLOW_COMBINATORIAL_LOOPS TRUE to pass combinatorial loops?

    Dear all,

    While I was searching for a solution that I have like this in Vivado, I have a problem of the combinatorial loop in my design targeting design of a ring oscillator. Can anyone please let me know in the following command what should I add in my xdc file to make it run?? [get_nets] ?? [get_pins] ?? [get_ports] ?? or etc. ?? I did all trials but it does not work !!
    Thank you so much,

    set_property ALLOW_COMBINATORIAL_LOOPS TRUE ...??

    •   Alt14th July 2017, 23:41

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  2. #2
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    Re: How to apply set_property ALLOW_COMBINATORIAL_LOOPS TRUE to pass combinatorial lo

    Quote Originally Posted by msdarvishi View Post
    Dear all,

    While I was searching for a solution that I have like this in Vivado, I have a problem of the combinatorial loop in my design targeting design of a ring oscillator. Can anyone please let me know in the following command what should I add in my xdc file to make it run?? [get_nets] ?? [get_pins] ?? [get_ports] ?? or etc. ?? I did all trials but it does not work !!
    Thank you so much,
    combinational loops make the tools go crazy because they can't time. it's either poor coding or an exercise in futility.
    Really, I am not Sam.



    •   Alt15th July 2017, 03:58

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  3. #3
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    Re: How to apply set_property ALLOW_COMBINATORIAL_LOOPS TRUE to pass combinatorial lo

    Quote Originally Posted by ThisIsNotSam View Post
    combinational loops make the tools go crazy because they can't time. it's either poor coding or an exercise in futility.
    So, what is the solution?? How can it let us process with our design when we must have a mandatory combinatorial loop like ring oscillators in our design? What should be written in front of my earlier post to let the tool to execute it??



    •   Alt15th July 2017, 04:09

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  4. #4
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    Re: How to apply set_property ALLOW_COMBINATORIAL_LOOPS TRUE to pass combinatorial lo

    No one builds an FPGA design with ring oscilators.
    Really, I am not Sam.



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