TESTING DEVICE USING FRAME TYPE KNOWLEDGE EXPRESSION

PURPOSE:To decide whether an output signal is normal or not by describing cards in equipment to be tested in frame structure, one by one, and tracing connections between the cards automatically. CONSTITUTION:A frame editor traces connections between cards automatically to determine an input signal value required to decide whether the output signal of a specified card frame is normal or not. All inputs signals are obtained and then the function of the card is evaluated to calculate a signal value to be outputted. When the output signal is observed actually, the observed value and calculated value are compared immediately, but when not, a card which outputs the output signal is searched for and decision making operation is performed again for the card. This operation is repeated until the observation output signal is reached, and the observed and calculated values are compared with each other. When the output signal is correct, cards which are passed so far are all normal and when not, it is decided that they are defective.