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//////////////////////////////////////////////////////////////////////

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//// Copyright (C) 2018 Authors and OPENCORES.ORG                 ////

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//////////////////////////////////////////////////////////////////////

// --------------------------------------------------------------------

 typedef enum

 {

    NONE,

    SPORADIC,

    // BURSTY,

    REGULAR

 } random_delay_type_e;

// --------------------------------------------------------------------

class random_delay;

  rand int unsigned delay = 0;

  time wait_timescale = 1ns;

  // --------------------------------------------------------------------

  virtual function void set_delay(random_delay_type_e kind = REGULAR);

    case(kind)

      NONE:     delay = 0;

      SPORADIC: assert(this.randomize() with{delay dist {0 := 96, [1:3] := 3, [4:7] := 1};});

      REGULAR:  assert(this.randomize() with{delay dist {0 := 60, [1:3] := 30, [4:7] := 10};});

      default:  delay = 0;

    endcase

  endfunction: set_delay

  // --------------------------------------------------------------------

  virtual task next(random_delay_type_e kind = REGULAR);

    set_delay(kind);

    #(delay * wait_timescale);

  endtask: next

  // --------------------------------------------------------------------

  virtual function int unsigned get(random_delay_type_e kind = REGULAR);

    set_delay(kind);

    return(delay);

  endfunction: get

// --------------------------------------------------------------------

endclass: random_delay