| 摘要 |
PURPOSE:To detect not only a data error but also an error of a control circuit, etc., by dividing a circuit to be checked into plural sub-circuits, controlling separately each sub-circuit by each independent control circuit, and constituting a titled circuit so that output data of plural sub-circuits are brought to a parity check as a whole. CONSTITUTION:A circuit to be checked 3 divides and inputs data A of 8 bit (A0-A7) and its parity bit Ap, and data B of 8 bit (B0-B7) and its parity bit Bp to two sub-circuits 4 and 5, respectively. The sub-circuit 4 consists of a selecting circuit 7 of a 4 bit portion two inputting circuit and a register 9, and the sub- circuit 5 consists of a selecting circuit 8 of a 5 bit two inputting circuit and a register 10, and they are controlled independently by control circuits 1, 2, respectively. Register output signals 60, 61 of the register 9 and 10 are inputted to a parity checking circuit 6, and for instance, the number of ''1'' of the data A0- A7 and its parity bit Ap is checked, and the normal property of the data and the operation is checked. |
