| 摘要 |
PURPOSE:To easily evaluate the error processing by inverting the input of one of two duplex computing elements with firmware for generation of an error. CONSTITUTION:A computing element B 6 which uses the outputs of a register X 1 and a selector 5 as inputs performs the same operation as a computing element A 3. Thus the elements B 6 and A 3 are duplex in order to confirm the correct arithmetic result of the element A 3. A comparator 7 compares the arithmetic results of both elements A 3 and B 6 with each other and outputs a comparison error signal (b) when no coincidence is obtained between both arithmetic results. The selector 5 usually selects the value of a register Y 2 and also selects the output of an inverter 4 with a selection signal (a) obtained under the control of firmware. Thus the value of the register Y 2 is inputted to the element A 3, and the inverted value of the register Y 2 is inputted to the element B 6 respectively. As a result, no coincidence is obtained between the arithmetic results of both computing elements and the signal (b) is outputted from the comparator 7. |
