  The article describes an attempt to solve at once three basic problems
arising at testing a complex digital equipment for defects: 1) the problem of
an exponential increasing of the complexity of testing the equipment with the
complexity of the equipment; 2) the problem of testing of the tester; 3) the
problem of a mutual masking of defects. The proposed solution is nothing more
than using certain limitations for connections between usual logical gates.
Arbitrary multiple stuck-at-faults are supposed as defects.
