| 摘要 |
PURPOSE:To designate a conditional branch instruction in a microinstruction which designates a return address to be saved, by using another bank address, which pairs up together with the address of this microinstruction, as the return address. CONSTITUTION:When a microinstruction in address J+1 is held in a microinstruction register 5, it is tested in a test condition deciding part 7 in accordance with a test condition designating part T whether contents of a part B are 0 or not, and a decoder 6 uses the control code in a part C to indicate the saving operation to a save register 8. Since address registers 2 and 3 indicate address J+1, inverted bank bits of address registers 2 and 3 are saved in the save register 8, and as a result, address J is saved in the save register 8. In case of B=0, a microinstruction in address N+1 is executed to branch to a subroutine ''SUB2'', and the control is returned to address J of a main routine ''MAIN'' by the last microinstruction of this subroutine. |
