UVM · Topic
UVM Scoreboards — Reference Models & Checking Strategy
Building a scoreboard — reference model, transaction matching, out-of-order handling, and the end-of-test checks most suites omit.
A scoreboard is the only component whose failure is invisible: when it stops checking, everything goes green. That shapes how one should be built. A comparison written with `!=` returns X on an unknown DUT output and takes the else branch, reporting a pass on exactly the data most likely to be a bug. A reference model that shares a type definition or a helper routine with the DUT cannot catch an error in the shared code. And a scoreboard with no `check_phase` never notices that it received nothing at all.