Abstract: A hybrid controller is used to control a plurality of relays, within a switching matrix, for effecting connection of an equipment under test to at least one of a plurality of test instruments. To do so, the hybrid controller utilizes latch drivers which are capable of driving 24 relays simultaneously. To check whether or not the correct relay is activated, drivers are used to sense the statuses of the relays and forward the information to a central processing unit for comparison. The drivers are controllably actuated by a decoder means, which in turn is controlled by the central processor.

Abstract: A number of standardized microprocessors are used as building blocks for gaining access and control to other standardized functional resource circuit units. One of the microprocessors is selected by a main processing unit to capture the different functional resource circuit units needed to perform functions of a discrete test instrument. To instruct the different resource circuit units to perform the needed functions, a program is downloaded from a mass memory by the microprocessor. After having performed the necessary functions, the microprocessor releases the different functional resource circuit units, which--along with the microprocessor--would return to idle and await the next selection.

Abstract: The signal distribution function in a signal distribution system is performed in a switching matrix under the control of a hybrid controller. With respect to the switching matrix, there are approximately 120-140 available interface I/O connections such that an equipment under test can be selectively connected to any one of a plurality of test instruments. The relays within the switching matrix are selectively activated such that a signal path connecting the equipment under test to a particular test instrument can be accomplished with a minimum amount of switching path conflicts.