The present disclosure generally relates to the automated testing of a system that includes software or hardware components. In some embodiments, a testing framework generates a set of test cases for a system under test using a grammar. Each test case may perform an action, such as provide an input to the system under test, and result in an output from the system under test. The inputs and outputs are then compared to the expected results to determine whether the system under test is performing correctly. Specifically, the system under test may be analyzed to determine whether it is capable of properly processing control instructions and input signals and/or generating expected output control signals and additional control/feedback information. The data can then be interpreted in the grammar system and/or used as input to a fault isolation engine to determine anomalies in the system under test.