| 摘要 |
PURPOSE:To obtain an electronic circuit block testing circuit which can be composed of a comparatively small circuit for test and can monitor real operations as well without requiring a lot of test patterns concerning the test of an electronic circuit. CONSTITUTION:When an input address 6 is a prescribed address value an input address identification circuit 2 generates an input switching signal 7 at every block 1 of the electronic circuit, and an input switching circuit 3 is connected so as to selectively input either normal input data 8 or test input data 9 to the block 1. Only when the input switching signal 7 is received, the test input data 9 are inputted to the block 1, and an output address identification circuit 4 receives the input of an output address 10. When the output address 10 is a prescribed address value, an output switching signal 11 is generated and an output switching circuit 5 is connected so as to selectively output either normal output data 12 or test input data 9 only. Only when the output switching signal 11 is received, the normal output data 12 are outputted. |
