USE IEEESTD_LOGIC_1164ALL; --程序中有STD_LOGIC和STD_LOGIC_VECTOR数据类型这两种数据类型都在STD_LOGIC_1164 --程序包中定义。USE IEEESTD_LOGIC_UNSIGNEDALL; --程序中有+运算符无符号数的算术运算在STD_LOGIC_UNSIGNED程序包中定义。ENTITY BAIFENPING

`timescale 1ns/1ns

module BAIFENPING (
    input wire CLR, CLK_SOURCE,
    output reg CLK_TARGET
);

reg [5:0] CNT;
parameter M = 49;
reg TMP;

always @(posedge CLK_SOURCE or negedge CLR) begin
    if (CLR == 0) begin
        CNT <= 6'b000000;
        TMP <= 1'b0;
    end else if (posedge CLK_SOURCE) begin
        if (CNT == M) begin
            TMP <= ~TMP;
            CNT <= 6'b000000;
        end else begin
            CNT <= CNT + 1;
        end
    end
end

assign CLK_TARGET = TMP;

endmodule
``