企业官网建设流程全解析

1、题目

The game Lemmings involves critters with fairly simple brains. So simple that we are going to model it using a finite state machine.

In the Lemmings' 2D world, Lemmings can be in one of two states: walking left or walking right. It will switch directions if it hits an obstacle. In particular, if a Lemming is bumped on the left, it will walk right. If it's bumped on the right, it will walk left. If it's bumped on both sides at the same time, it will still switch directions.

Implement a Moore state machine with two states, two inputs, and one output that models this behaviour.

See also: Lemmings2, Lemmings3, and Lemmings4.

2、分析

旅鼠游戏：旅鼠只能向左或向右走，撞到前进方向的障碍物就会改变方向。（注意撞到非前进方向的障碍物不改变方向）

3、代码实现

module top_module( input clk, input areset, // Freshly brainwashed Lemmings walk left. input bump_left, input bump_right, output walk_left, output walk_right); // parameter LEFT=0, RIGHT=1;//定义状态 reg state, next_state; //状态转换，下一个状态 always @(*) begin case(state) LEFT:begin if(bump_left) next_state=RIGHT; else next_state=LEFT; end RIGHT:begin if(bump_right) next_state=LEFT; else next_state=RIGHT; end endcase end //状态寄存器 always @(posedge clk, posedge areset) begin if(areset) state<=LEFT; else state<=next_state; end //输出 assign walk_left = (state ==LEFT); assign walk_right = (state ==RIGHT); endmodule

4、结果