| 摘要 |
PROBLEM TO BE SOLVED: To simplify the scale of hardware at the time of evaluating an error with a reference value by operating the bit NOR of a checked numeric value on high-order digits more than the digit becoming '1' in the binary display of the reference value when the reference value is the specified numbered power of '2'. SOLUTION: A register 1 into which a base vale 1 is filled and a register 2 into which a base value 2 is filled are provided. The values are subtracted by a subtracter 3. A specified bit among the output bits is inputted to an NOR circuit 4. If the value X to be evaluated is an integer which satisfies 0<=X<=2N and which is binary-displayed when the reference value is a positive integer being the certain numbered power of '2', '1' is generally given only between the first digit and N-th digit, which are counted from a digit at the lowest location, and the digit at higher location than the (N+1)-th digit becomes '0'. If '1' is outputted from the NOR circuit 4 when the digit at higher location than the (N+1)-th digit is inputted to the NOR circuit among the outputs of the subtracter 3, it is judged that 0<=×2N. |
