PROGRAMMIERBARE LOGISCHE ANORDNUNG

An apparatus and a method to automatically locate defects and to automatically insert and personalize dummy lines in a PLA having latches controlling the cross points of the AND and OR array. Upon occurrence of an error in the PLA, a check signal is generated which interrupts normal operation of the PLA and which initiates a test procedure. The cross point latches are automatically loaded with test patterns and the output of the PLA is analyzed to locate the defective part, for example, a damaged cross point transistor, short circuited or open line. The dummy lines are repersonalized automatically to replace lines which are defective themselves or which are connected to defective crosspoints.