Where does the random variables in the sequencer are randomized?

UVM
,
1

Say i have a basic sequence like this where i want to randomize the mode in the sequence in my test. Please note I am ignoring boiler plate code for brevity. I am very particular that i want to start my sequence this way. I have embedded my questions in the code using comments. Please clarify.


class foo_seq extends uvm_sequence #(my_seq_item);
    rand bit [3:0] mode;
    task body();
        case (mode)
           0 : //do mode 0 specific randomization in the sequence item
           1 : //do mode 1 specific randomization in the sequence item
               //so on so forth
        endcase
    endtask
endclass
class test extends uvm_test;
   task run_phase();
      //now when i want to start my sequence like below. 
      //Does mode get randomized automatically? If so in which part of start() it gets randomized()?
      //Or do I need to call my_foo_seq.randomize() first before calling my_foo_seq.start(...)
      //note that i am particular about randomizing this mode variable in my sequence.
      my_foo_seq.start(my_foo_seqr);
   endtask
endclass
2

In reply to srshan_rocks:

When you are starting your sequence without randomizing it mode will not be randomized.

3

In reply to chr_sue:
Thanks. That explains it!

4

In reply to srshan_rocks:
You can also put the call to randomize in the new or body methods of foo_seq, as well as using randcase.