Abstract: The invention is directed to techniques for accessing an external device, e.g., a device under test (DUT), from an automatic test equipment (ATE) interfacing apparatus, e.g., a specialized tester or channel card device. In one arrangement, the ATE interfacing apparatus includes a test bus interface for connecting to a test bus of an automatic test system; an external device interface for connecting to an external device; and a translator, interconnected between the test bus interface and the external device interface. The translator receives a memory access instruction from the test bus through the test bus interface. The memory access instruction includes a command and a test bus address. The translator translates the test bus address into an identifier which identifies a portion of the external device, and accesses the identified portion of the external device through the external device interface based on the command and the identifier.