1. In an artificial neural network (ANN) classifier system having n class output terminals comprising n processing output terminals indicative of n classes, with one of said class output terminals activated for a given set of feature input vectors associated with that class, said system including a computer capable of implementing a predetermined subroutine as a function of an activated output class and said computer having at least one interrupt input terminal, in combination therewith apparatus for accessing said computer, comprising: means coupled to said class output terminals and to said interrupt input and operative to energize said interrupt input terminal upon activation of one of said n processing output terminals for causing said computer to provide a subroutine according to which one of said n class output terminals is activated.