原创 奇数分频--或--3分频

module Freq_div(clk,rst,out);
 input clk;
 input rst;
 output out;
 reg out1;
 reg out2;
 reg[1:0] cnt1;
 reg[1:0] cnt2;

always@(posedge clk or negedge rst)
 if(!rst)
  begin
  cnt1<=2'b00;
  out1<=1'b0;
  end
 else if(cnt1==2'b10)
  begin
  cnt1<=2'b00;
  out1<=out1;
  end
 else
  begin
  cnt1<=cnt1+1'b1;
  out1<=~out1;
  end
  
always@(negedge clk or negedge rst)
 if(!rst)
  begin
  cnt2<=2'b00;
  out2<=1'b0;
  end
 else if(cnt2==2'b10)
  begin
  cnt2<=2'b00;
  out2<=out2;
  end
 else
  begin
  cnt2<=cnt2+1'b1;
  out2<=~out2;
  end
assign out=out1 | out2;
endmodule