Abstract: A system (10) for testing one or more circuit boards (12.sub.1 -12.sub.n), each containing at least one chain of Boundary-Scan cells (14.sub.1 -14.sub.p), includes a system test and diagnosis host (16) for managing overall testing of the system formed by the circuit boards. A Boundary-Scan Virtual Machine (BVM) (17) is operative to receive an initiate test command from the system test and diagnosis host independent of the number and nature of the boards to be tested. In response to the test command, the BVM (17) causes each circuit board to execute a test program (23) specific thereto to determine the errors, if any, in the board. The errors from each board are passed back to the BVM (17) which, in turn, interprets the errors to yield test information, indicative of the operation of the boards, which is then passed back to the system test and diagnosis host (16).