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module test2(input clk, input rst, output tx);
    localparam NEXT = 4'b0000;
    localparam DONE = 4'b1111;
    reg [7:0] r;
    reg [3:0] n;
    reg [7:0] char;
    reg [3:0] state = NEXT;
    reg send = 0;
    reg [23:0] cnt;
    wire clk2 = cnt[13];
    tx1 tx1(.clk(clk), .rst(rst), .send(send), .data(char), .tx(tx), .ed(ed));
    always @(posedge clk)
    begin
        cnt <= cnt + 1'b1;
    end
    always @(posedge clk2)
    begin
        send <= 0;
        if (ed)
        begin   
            if (rst == 0)
            begin
                state <= NEXT;
                r <= 234;
                n <= 0;
            end
            else if (state == NEXT)
            begin
                r <= r * 5 + 1;
                state <= 1;
            end
            else if (state != DONE)
            begin
                if (n == 4)
                begin
                    case (state)
                    1:
                    begin
                        char <= "d";
                        state <= state + 1;
                    end
                    2:
                    begin
                        char <= "o";
                        state <= state + 1;
                    end
                    3:
                    begin
                        char <= "k";
                        state <= state + 1;
                    end
                    4:
                    begin
                        char <= "o";
                        state <= state + 1;
                    end
                    5:
                    begin
                        char <= "k";
                        state <= state + 1;
                    end
                    6:
                    begin
                        char <= "i";
                        state <= state + 1;
                    end
                    7:
                    begin
                        char <= "y";
                        state <= state + 1;
                    end
                    8:
                    begin
                        char <= "o";
                        state <= state + 1;
                    end
                    9:
                    begin
                        char <= "s";
                        state <= state + 1;
                    end
                    10:
                    begin
                        char <= "i";
                        state <= DONE;
                    end
                    endcase
                end
                else if (r < 127)
                begin
                    case (state)
                    1:
                    begin
                        char <= "z";
                        state <= state + 1;
                    end
                    2:
                    begin
                        char <= "u";
                        state <= state + 1;
                    end
                    3:
                    begin
                        char <= "n";
                        state <= state + 1;
                    end
                    4:
                    begin
                        char <= " ";
                        n <= n + 1;
                        state <= NEXT;
                    end
                    endcase
                end
                else 
                begin
                    case (state)
                    1:
                    begin
                        char <= "d";
                        state <= state + 1;
                    end
                    2:
                    begin
                        char <= "o";
                        state <= state + 1;
                    end
                    3:
                    begin
                        char <= "k";
                        state <= state + 1;
                    end
                    4:
                    begin
                        char <= "o";
                        state <= state + 1;
                    end 
                    5:
                    begin
                        char <= " ";
                        n <= 0;
                        state <= NEXT;
                    end
                    endcase
                end
                send <= 1;
            end
        end
    end
endmodule