2-255倍四路输出分频器~~互相学习

module frediver(
    input clkin,
    input en,
    output reg freq1out = 1'b0,
    output reg freq2out = 1'b0,
    output reg freq3out = 1'b0,
    output reg freq4out = 1'b0
);
parameter denominator1 = 3;
parameter denominator2 = 4;
parameter denominator3 = 6;
parameter denominator4 = 8;


reg [7:0] cal1 = 8'b0;
reg [7:0] cal2 = 8'b0;
reg [7:0] cal3 = 8'b0;
reg [7:0] cal4 = 8'b0;

always@(clkin or en)
begin
    if( en )
    begin
    cal1 <= (cal1 == denominator1 - 1  ? 8'b0 : (cal1 + 8'b1));
    cal2 <= (cal2 == denominator2 - 1  ? 8'b0 : (cal2 + 8'b1));
    cal3 <= (cal3 == denominator3 - 1  ? 8'b0 : (cal3 + 8'b1));
    cal4 <= (cal4 == denominator4 - 1  ? 8'b0 : (cal4 + 8'b1));
    freq1out <= (cal1 == (denominator1 - 2) ? ~freq1out : freq1out);
    freq2out <= (cal2 == (denominator2 - 2) ? ~freq2out : freq2out);
    freq3out <= (cal3 == (denominator3 - 2) ? ~freq3out : freq3out);
    freq4out <= (cal4 == (denominator4 - 2) ? ~freq4out : freq4out);
    end
end
endmodule

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