Randomization

hello seniors,

in my Testbench one input size with 4 bit,
in transaction class i Randomize this 4 bit input using “rand” keyword,
but in simulation result input showing only one cobnination while it should show all possible combination of 4bit input means 16.
please tell me why apart from 1 combination rest 15 combination not randomizing.

Thanks in advance

In reply to uvm_verification:

Without seeing your code, we can not help. Please provide a complete example which shows your issue.

In reply to cgales:

As Chuck says, we need to see something. Are there any constraints on this input? Can you put a $display in post_randomize() to see if the value is changing. If it is change there, but not in your DUT, you have a completely different problem unrelated to randomization.