Abstract: A SCSI bus backplane interface coupled between a host system and a SCSI bus backplane is used to functionally test the backplane. The interface allows the backplane to be disconnected and exchanged for another backplane while avoiding interruption of the operation of the host system and avoiding powering down a cluster of drives present at the interface. The interface intercepts the SCSI bus termination signal during backplane exchange and re-establishes it to the drives (the SCSI bus) after the exchange is made. Complete isolation between the host system, the backplane, and the drives during power cycling permits the backplane to be exchanged without damage. Host system BIOS reboot recognition of the drives is not required each time the backplane is replaced, or to establish the number of active drives to functionally test each backplane after replacement. Test time is therefore reduced.

Abstract: The present invention includes a method and apparatus for performing intrusive testing upon a microprocessor to ensure the absence of errors or defects in performance-enhancing features and related control circuitry which affect the results of software instructions being executed by the microprocessor. In the intrusive testing method, an intrusive testing unit capable of generating logic signals is coupled between a computer system motherboard and a microprocessor. The microprocessor is then caused to execute a test software program. As the microprocessor executes the test software program, the intrusive testing unit generates logic signals (alternate control signals) at regular intervals. Control signals generated by system hardware on the motherboard in response to program execution are logically combined with alternate control signals generated by the intrusive testing unit. Resulting output control signals are applied to the control signal pins of the microprocessor.