| 摘要 |
PURPOSE:To search a fault, etc. in a short time, by preserving the final address of a microprogram during a hang-up mode of an idle routine and then analyzing the preserved address. CONSTITUTION:A flag is set up when a link to an idle routine is formed to a flag bit provided in a microinstruction. A flag deciding circuit 6 decides the flag bit and opens a gate 8 when a flag is set up to set the contents of a microprogram address register 2 to a control register 10. At the same time, the data read out to an instruction register 4 is decoded 5. Therefore the address of the idle routine is set to the register 2 after a prescribed microinstruction is executed. Then the data is read out of an ROM3, and the idle routine is executed. |
