| 摘要 |
PURPOSE:To control branching operation and the operation of various hardware simultaneously with one microinstruction word by attaining access to a control storage device by reading out a branch address from an auxiliary control storage device while exercising hardware operation control except the branch operation. CONSTITUTION:In a control storage device 10, a microprogram which is a set of microinstruction words is stored, and an auxiliary control storage device 12 is divided by four into areas with levels 0-3 which can be specified by OP codes of user instructions. In the area with level 0, the address of the 2nd instruction word of the program is stored and in areas with levels 1-3, branch addresses are stored. Through a selector switch 2 receiving OP codes, the operation of hardware except branching operation is performed and the OP code are supplied to a selector switch 9 via a register 8 to select the OP code. Then, the branch address is read out from the device 12 and applied to the switch 2 to control the branching operation and various hardware operation simultaneously with one instruction word. |
