Fetching system of macroinstruction

Abstract

Abstract PURPOSE:To increase the fecthing speed of a macroinstruction, by storing the programs to different memories in response to the executing frequency of these programs. CONSTITUTION:An applied program comprising macroinstruction groups is stored in a main memory 1, and the memory 1 is connected to a system bus 3 via a memory controller 2. A control program of OS comprising macroinstruction groups and having a high executing frequency is stored in a high-speed memory 4 and then connected to a bus 3 via a memory controller 5. A fetching destination designating register 6 designates the fetching of a macroinstruction of the memory 1 or 4. The output lines S1 and S2 of the register 6 are controlled to be set at logic 1 with a microinstruction. Then a selector 7 selects a register 10 to which the instruction fed from the memory 1 is transferred, and this instruction is fed to a decoder 8. When a macroinstruction which calls out a control program is fetched, the lines S1 and S2 are set at logic O. Then the selector 7 selects a register 12 to which the instruction from the memory 4 is transferred. In this case, an interruption, mask register 13 is locked, and an external interruption request is masked.

Inventors

• 👤 Masami Takada
• 👤 高田　正実

Bibliographic Details