设计一个6层电梯控制器。电梯控制器是按照乘客的要求自动上、下的装置。

1、每层电梯入口处设置上下请求开关，电梯内设有顾客到达层次的停站请求开关。

2、设有电梯所处位置指示装置以及电梯运行模式（上升或者下降）指示装置。

3、电梯每秒升降一层楼。

4、电梯到达有停站请求的楼层，经过1秒电梯门打开，开门4秒后，电梯门关闭（开门指示灯灭），电梯继续运行，直至执行完最后一个请求信号后停留在当前层。

5、电梯能记忆电梯内外所有请求信号，并按照电梯运行规则按顺序响应，每个请求信号保留至有电梯响应后消除。

6、初始状态为一层开门，第一层不用向下开关，最高层不用向上开关。

7、电梯运行规则：当电梯上升时，只响应比电梯所在位置高的上楼请求信号，由下而上逐个执行，直到最后一个上楼请求执行完毕；如果高层有下楼请求，则直接升到下楼请求的最高楼层，然后进入下降模式。当电梯处于下降模式时与上升正好相反。

-design of a six-story elevator controller. Elevator Controller in accordance with the requirements of passengers automatically, the device. 1, installed on each floor elevator entrance next request switches, elevator begins to reach the level of customer stops request switch. 2, the location of elevator and escalator installations instructions operation mode (up or down) device instructions. 3, Elevator per second floor landing. 4, the lift reached a request stops floors seconds after an elevator doors open door four seconds later, elevator doors closed (to open the door to eliminate light), the continued operation of the lift, End until the implementation of the final request for a signal to stay in the current layer. 5, the lift will lift internal and external memory signal to all reques