| 摘要 |
PURPOSE:To automatically select a general-purpose register used for the next instruction based on the executing result of an arithmetic operation preceding by one step by using a selector circuit to obtain a signal from a status register for selection of a register used for arithmetic operations, etc. CONSTITUTION:A status register 2 stores the flag information on 0, the minus, etc., obtained by the arithmetic results of an ALU 13. Then the register 2 sends the m-bit information to a selector 7 and at the same time an instruction register 1 sends the m-bit information to the selector 7. The selector 7 selects either one of both m-bit information received from both registers 1 and 2 based on the 1-bit information (selection signal 5) taken out of the register 1. Then the selected m-bit information is given to a general-purpose register group 11 via a decoder 9 and either one of registers 11 is selected by a selection signal 10. |
