| 摘要 |
PURPOSE:To prevent the runaway of a program in failure, by reading out a microinstruction from a control memory through an advanced address at all time when the operating mode serves as a diagnostic mode. CONSTITUTION:The address of a control memory storing a microinstruction is applied to a control memory CM via address selection circuits SELA, SELB. The microinstruction from the memory CM is temporarily stored to a register CMIR. The address of the next microinstruction is determined with a control circuit CTL. The output of an address counter MCP is connected to the selection circuits SELA, SELB, and the output of the selection circuit SELA is connected to the circuit SELB and a diagnostic resister DREG. The input of the SELA is selected either by a sequence mode field determining the address of the next instruction in the microinstruction during the present execution or interruption. |
