| 摘要 |
PURPOSE:To prevent a hardware from becoming large and to prevent a processing cycle from increasing by making the number of bits of a data processed with an ALU less than that of a program address and transmitting a carrying signal through a selective part to a high-order increasing/decreasing device. CONSTITUTION:This unit is equipped with an ALU 19 which processes the data consisting of the number of bits less than that of the program address data, plural increasing/decreasing devices 51 - 53 which make it possible to increase or decrease selected constant, selective parts 25 and 26 which transmit the selected carrying signal to the high-order increasing/decreasing devices 51 - 53 and registers 54 - 56. When the carrying system is generated after a part of the divided program address is calculated by the ALU 19, the carrying signal is transmitted to the other divided program addresses so that the ALU 19, the increasing/decreasing devices 51 - 53 and the selective parts 25 and 26 can generate the program address in one cycle after branching. Thus, the hardware is prevented from becoming large and the processing cycle is prevented from increasing. |
