| 摘要 |
PURPOSE:To facilitate a test and also to improve the efficiency of use of silicon by a construction wherein an input circuit formed of a switch or latch circuit and a control circuit thereof are provided in a part wherein a discrete logic circuit block receives an input signal from a bus. CONSTITUTION:A control signal inputted from a control signal terminal 9 is supplied by a control line 8 to control circuits 3(3-1 to 3-n) controlling input circuits 2(2-1 to 2-n) of all logic circuit blocks 1(1-1 to 1-n). According to this control signal, all of the circuits 3 receive data from a bus 7, all at once, through the corresponding circuits 2 and signal lines 3a. Based on these data, each of the circuits 3 determines whether the block 1 controlled thereby is an object of a test, and in accordance with this determination, it connects a signal line between the bus and the circuit 2 or between the circuit 2 and the block 1 when the block 1 is the object of the test, while it disconnects the line when the block is not the object, and operates so that the block is put in a state of stoppage. |
