Abstract: A host register interface testing system and method are disclosed. The system includes a host register unit including information that is indicative of a set of host registers corresponding to a programmable device under test. The system further includes a rule set unit including information that is indicative of constraints on values that the set of host registers may assume and a test setup generator configured to access the host register unit and the rule set unit and to generate a set of test setups based on the contents of the host register unit and the rule set unit where each test setup corresponds to a valid state of the set of host registers. In one embodiment, the test setup generator is suitable for applying a test setup from the set of test setups to the device under test. In one embodiment, the system may further include a verifier configured to receive the output of the device under test and, based thereon, for determining the functionality of the device under test.