JP2766901B

PURPOSE:To simplify a program for actuating a pattern generator by omitting the requirement for the output of an address signal for accessing a defect analysis memory from the pattern generator. CONSTITUTION:An address pointer 8 and a selector 9 are added to a defect analysis memory 7. When a memory under test 5 is an element which does not require the supply of an address signal (a), the selector 9 is switched into an input terminal B. The address signal which is outputted from the pointer 8 is imparted to the memory 7. In this way, in the defect analysis memory 7, the same address as in the memory under test 5 is accessed. When disagreement between the read-out data (d) and an expected value signal (e) is detected in a comparator 6, a '1' which expresses the defect can be written in the same address in the defect analysis memory 7 wherein the disagreement has occurred.