Systemverilog introductes additional system tasks to aid randomization, which are not CPU intersive, basically very fast compared to object randomization.

• $urandom_range : The $urandom_range() function returns an unsigned integer within a specified range.
• $urandom : The system function $urandom provides a mechanism for generating pseudo-random numbers. The function returns a new 32-bit random number each time it is called. The number shall be unsigned.
• $srandom : The srandom() method allows manually seeding the RNG of objects or threads.
• $set_randstate :The set_randstate() method sets the state of an object’s RNG.
• $get_randstate : The get_randstate() method retrieves the current state an object’s RNG.

  1 module system_random();
  2 
  3 initial begin
  4  // Set the seed
  5  $srandom(10);
  6  // Randomize number between 1 and 10
  7  $display ("Value is %0d",$urandom_range(10,1));
  8  // Use seed 10 before randomize
  9  $display ("Value is %0d",$urandom(10));
 10 end
 11 
 12 endmodule

 Value is 7
 Value is 1259199836

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