| 摘要 |
PURPOSE:To enable improvement of a rate of detection of a fault by a few additive circuits, by providing a means of outputting a plurality of functions of functional elements on the basis of coded information and by reading the outputs on the outside. CONSTITUTION:Circuits 11a to 11c for coding functions added to functional elements 10a to 10c are provided in a data path unit 1a. In addition, a function detecting unit 12 composed of an element specifying register 12b, a function register 12a and a function bus 12c is provided in a control unit1b. A functional information (1) determining primarily the discrete function that each of the elements 10a to 10c has is coded by the circuits 11a to 11c and sent to the register 12a through the bus 12c. Then, a logic circuit of each of the element group 10a to 10c specified by the register 12b is made to operate by using a test pattern set beforehand, the information (1) outputted from the register 12a is read, and when it is not in accord with an expected value, this is recognized as a fault. According to this constitution, a test can be facilitated. |
