1/2占空比的五分频电路实现

方法：先实现一个按时钟上升沿的五分频器，同样的分频方法，实现一个以下降沿触发的五分频器，然后把两个分频器的输出相或，就可以得到占空比为50%的五分频电路。`timescale 1ns / 1ps//////////////////////////////////////////////////////////////////////////////////// Company: // Engineer: // // Create Date:    09:56:59 07/09/2012 // Design Name: // Module Name:    fre // Project Name: // Target Devices: // Tool versions: // Description: //// Dependencies: //// Revision: // Revision 0.01 - File Created// Additional Comments: ////////////////////////////////////////////////////////////////////////////////////module fre(    input clk,    input reset,    output clko , output clk1 , output clk2     ); reg out1=0, out2=0 ; reg [2:0] count1= 0 ,count2 = 0   ;  always @ (posedge clk or posedge reset) begin if (reset)     count1 <= 0 ; else begincount1 <= count1 + 1 ; if (count1 == 2)  out1 <= ~out1 ;if (count1 == 4) begin   out1 <= ~out1 ;count1 <=0 ;   end   end end   always @ (negedge clk or posedge reset) begin if (reset)     count2 <= 0 ; else begincount2 <= count2 + 1 ; if (count2 == 2)  out2 <= ~out2 ;if (count2 == 4) begin   out2 <= ~out2 ;count2 <=0 ;   end   end end assign clk1 = out1 ; assign clk2 = out2 ; assign clko = out1|out2 ; endmodule