Subversion Repositories i2c_to_wb

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`timescale 1ns/10ps
 
 
module 
  glitch_generator
  #(
    parameter ENABLE = 0,
    parameter MAX_FREQ = 10000,
    parameter MAX_WIDTH = 120
  ) 
  (
    output out
  );
 
 
  // --------------------------------------------------------------------
  //  wires & regs
  reg glitch_generator_en;
  reg glitch;
  reg glitch_en;
 
 
  // --------------------------------------------------------------------
  //  init 
  initial
    begin
      glitch_generator_en <= ENABLE;
      glitch              <= 1'b0;
      glitch_en           <= 1'b0;
 
      forever
        begin: glitch_loop
 
          #({$random} % MAX_FREQ);
 
          if( ~glitch_generator_en )
            disable glitch_loop;
 
          glitch_en = 1'b1;
          #({$random} % MAX_WIDTH);
 
          glitch = ~glitch;
          #({$random} % MAX_WIDTH);
 
          glitch_en = 1'b0;
 
        end
    end      
 
 
  // --------------------------------------------------------------------
  //  enable_glitch_generator
  task enable_glitch_generator; 
    begin
 
    glitch_generator_en <= 1'b1;
 
    end    
  endtask
 
 
  // --------------------------------------------------------------------
  //  disable_glitch_generator
  task disable_glitch_generator; 
    begin
 
    glitch_generator_en <= 1'b0;
 
    end    
  endtask
 
 
  // --------------------------------------------------------------------
  //  outputs   
 
  assign (supply1, supply0) out = glitch_en ? glitch : 1'bz;
 
endmodule