按键消抖verilog代码
时间: 2023-12-08 16:05:38 浏览: 195
以下是Verilog实现按键消抖的代码示例:
```verilog
module debounce(
input clk, // 时钟信号
input rst, // 复位信号
input key, // 按键信号
output reg debounced_key // 消抖后的按键信号
);
reg [2:0] state; // 状态寄存器,用于记录按键状态
reg [31:0] cnt; // 计数器,用于延时
parameter IDLE = 3'b000; // 空闲状态
parameter PRESS = 3'b001; // 按下状态
parameter RELEASE = 3'b010; // 释放状态
parameter WAIT_PRESS = 3'b011; // 等待按下状态
parameter WAIT_RELEASE = 3'b100; // 等待释放状态
always @(posedge clk or posedge rst) begin
if (rst) begin
state <= IDLE;
cnt <= 0;
debounced_key <= 1'b1;
end else begin
case (state)
IDLE: begin
if (key == 1'b0) begin
state <= WAIT_PRESS;
cnt <= 0;
end else begin
state <= IDLE;
cnt <= 0;
end
end
PRESS: begin
if (key == 1'b1) begin
state <= WAIT_RELEASE;
cnt <= 0;
end else begin
state <= PRESS;
cnt <= 0;
end
end
RELEASE: begin
state <= IDLE;
cnt <= 0;
end
WAIT_PRESS: begin
if (key == 1'b0) begin
if (cnt < 32'd100000) begin
cnt <= cnt + 1;
end else begin
state <= PRESS;
cnt <= 0;
debounced_key <= 1'b0;
end
end else begin
state <= IDLE;
cnt <= 0;
end
end
WAIT_RELEASE: begin
if (key == 1'b1) begin
if (cnt < 32'd100000) begin
cnt <= cnt + 1;
end else begin
state <= RELEASE;
cnt <= 0;
debounced_key <= 1'b1;
end
end else begin
state <= IDLE;
cnt <= 0;
end
end
endcase
end
end
endmodule
```
该代码实现了一个按键消抖模块,包括状态寄存器、计数器和消抖后的按键信号输出。具体实现方法是通过状态机控制按键状态的转移,并在状态转移过程中进行延时,从而消除按键抖动的影响。
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