| 摘要 |
PURPOSE:To reduce the whole number of steps, not by registering a subroutine as a subroutime of a specific main routine but by using a part of a general microprogram in common to a subroutine. CONSTITUTION:The process of the 1st routine progresses, and the address information sent from an address register 3 is selected through a switching circuit 5. Then a microinstruction of an address (m) is read out of a control storage 1 to be stored in a microinstruction register 2. At the same time, an added 6 address m+1 is stored in the register 3. At this step, a step number 22 of the register 2, i.e., a process step number -1 of a microinstruction that is to be used in common when the 1st routine uses a part of the 2nd routine as the 1st shared part is stored in a step number register 8. In addition, a branch address 21 of the register 2, i.e., an address (n) is selected at the circuit 5. Thus the microinstruction of the address (n) is read out of the storage 1 and stored in the register 2 to carry out the branching to the 2nd routine. |
