“Draw compact gate-level logic for a two-floor elevator with CALL_1, CALL_2, AT_F1, AT_F2, and DOOR_CLOSED inputs. Output MOVE_UP for a floor-2 call from floor 1, MOVE_DOWN for a floor-1 call from floor 2, and DOOR_OPEN for a call at the current floor.”
看懂背後的決策。
MOVE_UP requires a floor-2 call, the car at floor 1, and a closed door.
MOVE_DOWN mirrors that logic for a floor-1 call from floor 2.
Each door-open term requires a matching call and at-floor signal.
A final OR gate combines the two door-open conditions.
This compact combinational example is suitable for introductory control logic. Real elevators also need interlocks, position sensing, timing, fault handling, and safety-certified equipment.
常見問題
Why is DOOR_CLOSED required for movement?
It models a basic permission condition so the circuit does not command travel with an open door.
What happens when the car is already at the called floor?
The matching door-open term asserts instead of either travel output.
Does this circuit remember a call?
No. It is combinational logic; request memory would require latches or flip-flops.