| 摘要 |
PURPOSE:To reduce the microprogram quantity by realizing a virtual 3-port register file and designating three types of registers stored in a register file with a single microinstruction. CONSTITUTION:The designated register numbers stored in the register files 2 and 3 are set in a C-E field of a microinstruction code 9. When an address '011' of a microinstruction shown in a diagram is carried out, the contents of the fields C, D and E show 0, 1 and 2 respectively. The data on a field C of the code 9 are led to the A ports of both files 2 and 3. Then the data DA1 and a DA2 on a register #0 designated by the field C are read out of the files 2 and 3. The data DA1 and the data DA2 read out of the register #0 are inputted to a data selector 7. Then either one of both data DA1 and DA2 is selected according to a level signal CLVL (0 or 1). |
