verilog實現N分頻電路

verilog實現N分頻電路：

module divn (
input clk,
input rst_n,
output o_clk
);

parameter WIDTH = 3;
parameter N = 6;

reg [WIDTH-1:0] cnt_p;
reg [WIDTH-1:0] cnt_n;
reg clk_p;
reg clk_n;

assign o_clk = (N == 1) ? clk :
(N[0]) ? (clk_p | clk_n) : (clk_p);

always@(posedge clk or negedge rst_n) begin
if (!rst_n)
cnt_p <= 0;
else if (cnt_p == (N-1))
cnt_p <= 0;
else
cnt_p <= cnt_p + 1;
end

always@(posedge clk or negedge rst_n) begin
if (!rst_n)
clk_p <= 1;
else if (cnt_p < (N>>1))
clk_p = 1;
else
clk_p = 0;
end

always@(negedge clk or negedge rst_n) begin
if (!rst_n)
cnt_n <= 0;
else if (cnt_n == (N-1))
cnt_n <= 0;
else
cnt_n <= cnt_n + 1;
end

always@(negedge clk or negedge rst_n) begin
if (!rst_n)
clk_n <= 1;
else if (cnt_n < (N>>1))
clk_n = 1;
else
clk_n = 0;
end

endmodule