PURPOSE: To facilitate verification of connection of a wire between a plurality of large microblock devices.

CONSTITUTION: During of large microblock devices 2 and 5 test for respective functions, a test terminal 25 is set to a '1' level. Thereby, a terminal B of a normal mode selecting test circuit 7 is connected to a terminal Y, the large microblock devices 2 and 5 are electrically disconnected from each other and individually tested. During varification of connection of a wiring 3 between the large microblock devices 2 and 5, a test terminal 24 is set to a '1' level. Thereby, a terminal B of each of interblock wiring varifying test circuits 3 and 6 is connected to a terminal Y, a signal from an input terminal 21 is outputted to an output terminal 28 and an output terminal 26. Thus, through confirmation of a signal from the output terminal 28 = a signal from the output terminal 26, connection of the wiring 3 can be varified.