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Altera_Forum's avatar
Altera_Forum
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17 years ago

is there a mechanism in verilog to validate parameter values?

I'm working on a very simple verilog module that has a parameter for the width of an input signal. I'll be using "[WIDTH-1:0] nomenclature for register instantiations, for instance..

Two questions:

1) What will happen if they try to pass me a value of "0" ?

2) More importantly-- how can I "validate" the value is a Natural number (1 or greater) at compile time and throw an error if a value less than 1 is passed?

thanks!

..dane

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Hi,

    1) Test it :-) and give answer. I think it not accepted by Quartus.

    2) In VHDL, I use assertions. there may be an equivalent in Verilog.

    ++
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Is it going to be a custom component in SOPC Builder? If it is, you can add ranges to generics in your hw.tcl file that will notify the user and stop him/her from generating the project if the value is outside the range.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    --- Quote Start ---

    Hi,

    1) Test it :-) and give answer. I think it not accepted by Quartus.

    2) In VHDL, I use assertions. there may be an equivalent in Verilog.

    ++

    --- Quote End ---

    1) wiseguy .. :) I knew I could test it -- but that only yields results very particular to one software (Quartus), and moreover, one version of that software (I'm using v7.2) ... I was hoping for a more "Verilog Lanugage Rules" type answer... :)

    Anyways, QII v7.2 gives the following error:

    Error (10232): Verilog HDL error at ***v(**): index 1 cannot fall outside the declared range [-1:0] for vector "****"

    2) Did some checking -- Verilog doesn't seem to support Assertions yet ... :( maybe we can hope for a future revision to include support..

    --- Quote Start ---

    Is it going to be a custom component in SOPC Builder? If it is, you can add ranges to generics in your hw.tcl file that will notify the user and stop him/her from generating the project if the value is outside the range.

    --- Quote End ---

    Nope-- not using SOPC builder this time around .. no need for this project.. thanks though!

    ..dane