| 摘要 |
PURPOSE:To facilitate an easy control of the jumping address for a microprogram control device, by making use of a set or reset terminal of a flip-flop that constitutes a program counter. CONSTITUTION:The program counter of a microprogram control device consists of a flip-flop. The set or reset terminal of the flip-flop is connected to the output of a microinstruction decoder to be used for the setting of the jumping address for the CALL instruction, the JUMP instruction and the like of the microinstruction. The diagram shows the n-th step circuit of a program counter. The signal exists on a line 13 in the case of a CALL instruction for instance, and thus a flip-flop 3 of the program counter is set. |
