Hi,

Can we be able to actually modify the disciplines.vams file. I mean just as we have an "electrical" discipline (which contains two natures - voltage and current), can we have an user defined nature and discipline.

To be more specific, i am right now trying to model a PLL. A PLL has a frequency divider circuit. Of course there are models available for that (for instance , there is one Ken Kundert's model available in the Designer's Guide website). But i thought that we could possibly define a nature for frequency and access it thro' some user defined disciplines. For this i added this piece of code in my "disciplines.vams" file.


nature Frequency
            units = "Hz"
            access = Fr;
`ifdef FREQUENCY_ABSTOL
            abstol = `FREQUENCY_ABSTOL
`else
            abstol = 1e-12;
`endif
endnature

/// Conservative discipline

discipline period
             potential Frequency;
enddiscipline


But when i actually executed this discipline in the following program it gave me error. this is the code where i used it.


// VerilogA for PLL_Prathap, Freq_Discipline_Check, veriloga

`include "constants.vams"
`include "disciplines.vams"

`include "/h/prathsi/disciplines_modified.vams"           -------- Location where the modified discipline file is present

module Freq_Discipline_Check(in, out);
input in;
output out;

period in;
voltage in;
period out;

real temp, temp_1;

analog begin

     @(cross(V(in)-0.1, 1)) begin
     
           temp = Fr(in);
           temp_1 = 10 * temp;
           Fr(out) <+ transition(temp_1, 10n, 10n, 10n);

     end
     
endmodule

What i have done might be completely incorrect. If so please try to correct/guide me.


Thanks You.

Regards,
Prathap.

You may be having a problem because you're including the default one and your modified one.

I find that some simulators will find "disciplines.vams" in your working directory instead of the standard include directory, or alternately you can just not `include "disciplines.vams" and instead `include your modified one, and make it contain only the disciplines/natures that you really want.

Why do you have "in" as both voltage and period?  What exactly is the error message you got?