and outputs a compare out signal 1008 pass fail scan memory 704 inputs the compare out signal 1008 compare strobe signal 613 scan input signal 611 scan control signals 612 and the test enable signal 609 and outputs the scan output signal 615 the test enable signal 609 is also input to trinary gate 701 xor gate 702 and and gate 1003 to reduce power consumption and noise during functional die operation as described previously in regard to comparator 608 the pass fail scan memory operates as previously described in regard to fig7 c the operation of compare circuit 908 is best understood via the truth table of fig1 b when the test enable 609 is low compare circuit 908 is disabled except for the scan cell 710 711 of pass fail scan memory 704 to enable sharing of the scan cell as both a pass fail indication scan cell and as an ieee 1149 1 boundary scan cell as mentioned in regard to fig7 c when test enable 609 is high the compare circuit 908 is enabled to perform testing according to the present invention while test enable 609 and output control 911 is high a gnd low encoded response input 914 from tester 401 causes trinary gate 701 to output a high on msk 706 and a low on exp 705 this test condition compares for an expected.