| 摘要 |
PURPOSE:To efficiently inspect a control storage even when micro-instruction holding registers are dispersed, by adding logical input circuits and logical output circuits having a bi-directional property of ternary logic to the route between the control storage and microinstruction holding registers. CONSTITUTION:A microinstruction read out of a control storage 10 is sent to an ECC microinstruction holding register 11 through comparator circuits 281-284, whose output is ternary one, and logical input circuits 291 and 194 and, at the same time, also inputted into microinstruction holding registers 16-18 through input circuits 312-314. As the output of a clock 40 advances, contents of the registers 11 and 16-18 change and the value of the register 11 is compared 45- 47 and supplied to FFs 42-44, where the value is subjected to error control. On the other hand, values of the registers 16-18 are compared 45-47 through logical output circuits 322-324, whose output is ternary one, and the logical input circuits 292-294 and supplied to the FFs 42-44, where the values are subjected to error control 41. Therefore, the control storage 10 can be inspected efficiently even when the registers are dispersed. |
