divider/rtl/divider_five0.v

module divider_five0(
    input  wire  sys_clk,
    input  wire  sys_rst_n,

    output reg   led
);
parameter MAX = 24'd10_000_000;
reg [2: 0]  cnt     ;
reg         clk1    ;
reg         clk2    ;
wire        clk     ;
reg [23: 0] cnt_clk ;
always @(posedge sys_clk or negedge sys_rst_n)begin
    if(!sys_rst_n)begin
        cnt <= 3'd0;
    end 
    else if(cnt == 3'd4)begin
        cnt <= 3'd0;
    end 
    else begin
        cnt <= cnt + 1'd1;
    end 
end 

//clk1根据上升沿改变
always @(posedge sys_clk or negedge sys_rst_n)begin
    if(!sys_rst_n)begin
        clk1 <= 1'b1;
    end 
    else if(cnt == 3'd2)begin
        clk1 <= 1'b0;
    end 
    else if(cnt == 3'd4)begin
        clk1 <= 1'b1;
    end 
    else begin
        clk1 <= clk1;
    end 
end 
//clk2根据下降沿改变
always @(negedge sys_clk or negedge sys_rst_n)begin
    if(!sys_rst_n)begin
        clk2 <= 1'b1;
    end 
    else if(cnt == 3'd2)begin
        clk2 <= 1'b0;
    end 
    else if(cnt == 3'd4)begin
        clk2 <= 1'b1;
    end 
    else begin
        clk2 <= clk2;
    end 
end 
assign clk = clk1 & clk2;
//时钟频率，10^9 / 100 = 10_000_000;
always @(posedge clk or negedge sys_rst_n) begin
    if(!sys_rst_n)begin
        cnt_clk <= 24'd0;
    end 
    else if(cnt_clk == MAX - 1'd1)begin
        cnt_clk <= 24'd0;
    end 
    else begin
        cnt_clk <= cnt_clk + 1'd1;
    end 
end

always @(posedge clk or negedge sys_rst_n)begin
    if(!sys_rst_n)begin
        led <= 1'b0;
    end 
    else if(cnt_clk == MAX - 1'd1)begin
        led <= ~led;
    end 
    else begin
        led <= led;
    end 
end 
endmodule