verilog实现一个5bit序列检测器
以下是用 Verilog 实现一个 5bit 序列检测器的代码:
module five_bit_sequence_detector(
input clk,
input reset,
input [4:0] in,
output reg detected
);
// 定义状态参数
localparam IDLE = 4'b0000;
localparam STATE1 = 4'b0001;
localparam STATE2 = 4'b0010;
localparam STATE3 = 4'b0011;
localparam STATE4 = 4'b0100;
localparam DETECTED_STATE = 4'b0101;
reg [3:0] current_state;
reg [3:0] next_state;
always @(posedge clk or posedge reset) begin
if (reset) begin
current_state <= IDLE;
detected <= 1'b0;
end else begin
current_state <= next_state;
if (current_state == DETECTED_STATE)
detected <= 1'b1;
else
detected <= 1'b0;
end
end
always @(*) begin
case (current_state)
IDLE:
if (in == 5'b00001)
next_state = STATE1;
else
next_state = IDLE;
STATE1:
if (in == 5'b00010)
next_state = STATE2;
else
next_state = IDLE;
STATE2:
if (in == 5'b00100)
next_state = STATE3;
else
next_state = IDLE;
STATE3:
if (in == 5'b01000)
next_state = STATE4;
else
next_state = IDLE;
STATE4:
if (in == 5'b10000)
next_state = DETECTED_STATE;
else
next_state = IDLE;
DETECTED_STATE:
if (in == 5'b10000)
next_state = DETECTED_STATE;
else
next_state = IDLE;
default:
next_state = IDLE;
endcase
end
endmodule
这个序列检测器检测特定的 5bit 序列 “00001”、“00010”、“00100”、“01000”、“10000”。当输入序列与这个特定序列匹配时,输出 detected
被置为高电平。状态机从初始状态 IDLE
开始,根据输入逐步进入不同的状态,直到检测到完整序列进入 DETECTED_STATE
。如果在任何状态下输入不匹配预期序列,状态机将回到 IDLE
状态重新开始检测。