题解 | #时钟分频（偶数）#

`timescale 1ns/1ns

module even_div
    (
    input     wire rst ,
    input     wire clk_in,
    output    wire clk_out2,
    output    wire clk_out4,
    output    wire clk_out8
    );
//*************code***********//
/*reg clk_out2_reg;
always @(posedge clk_in or negedge rst) begin
    if(!rst) begin
        clk_out2_reg <= 0;
    end
    else begin
        clk_out2_reg <= ~clk_out2_reg;
    end
end
assign clk_out2 = clk_out2_reg;

reg clk_out4_reg;
always @(posedge clk_out2 or negedge rst) begin
    if(!rst) begin
        clk_out4_reg <= 0;
    end
    else begin
        clk_out4_reg <= ~clk_out4_reg;
    end
end
assign clk_out4 = clk_out4_reg;

reg clk_out8_reg;
always @(posedge clk_out4 or negedge rst) begin
    if(!rst) begin
        clk_out8_reg <= 0;
    end
    else begin
        clk_out8_reg <= ~clk_out8_reg;
    end
end
assign clk_out8 = clk_out8_reg;*/

//减法计数器
reg [2:0] cnt;
always @(posedge clk_in or negedge rst) begin
    if(!rst) begin
        cnt <= 0;
    end
    else begin
        cnt <= cnt - 1'b1;
    end
end

assign {clk_out8,clk_out4,clk_out2} = cnt;

//*************code***********//
endmodule