You are an expert Verilog hardware designer working on a complete FPGA or ASIC project. You are given the full source code of a Verilog project. One of the modules in the project is incomplete — its implementation is missing and marked with:

// >>> Module Implementation Begin

// <<< Module Implementation End

Your task is to complete the missing implementation so that the entire project functions correctly. You must infer what the missing module or logic is supposed to do by analyzing the rest of the codebase: module names, signal connections, instantiations, comments, and usage patterns.

Follow these rules:

1. Only generate Verilog code to go between the `// >>> Module Implementation Begin` and `// <<< Module Implementation End` comments.
2. Use Verilog-2001 syntax. Ensure the code is synthesizable.
3. Assume the goal is a working, integrated hardware design — your code must make the whole system function as intended.
4. Analyze the naming, I/O ports, and how the module is instantiated or used in other parts of the project.
5. Implement correct behavior based on design context. Do not guess randomly — reason it out.
6. Avoid vendor-specific features unless explicitly required.
7. Do not output comments, explanation, or anything outside the required code region unless explicitly asked.

Your output should contain **only the Verilog code** that fits inside the marked region.

/*
 * Copyright (c) 2024 Your Name
 * SPDX-License-Identifier: Apache-2.0
 */

`default_nettype none

module tt_um_serdes (
    input  wire [7:0] ui_in,    // Dedicated inputs
    output wire [7:0] uo_out,   // Dedicated outputs
    input  wire [7:0] uio_in,   // IOs: Input path
    output wire [7:0] uio_out,  // IOs: Output path
    output wire [7:0] uio_oe,   // IOs: Enable path (active high: 0=input, 1=output)
    input  wire       ena,      // always 1 when the design is powered, so you can ignore it
    input  wire       clk,      // clock
    input  wire       rst_n     // reset_n - low to reset
);

  // All output pins must be assigned. If not used, assign to 0.
 
    
    wire ser_in = uio_in[0];
    wire ser_out = uio_out[0];
    wire data_en = uio_in[2];
    wire par_en = uio_in[3];
    wire ser_en = uio_in[4];

    serdes_top serdes_inst (
        .clk(clk),
        .rst_n(rst_n),
        .data_en(data_en),
        .ser_in(ser_in),
        .par_en(par_en),  
        .ser_en(ser_en),  
        .ser_out(ser_out),
        .data_out(uo_out),
        .data_8b_in(ui_in)  
    );
      assign uio_oe = 8'b0;  
    assign uio_out[7:1] = 7'b0;
endmodule


module serdes_top(
    input           clk,
    input           rst_n,
    input           data_en,
    input           ser_in,
    input           par_en,
    input           ser_en,
    output wire      ser_out,
    output wire [7:0]    data_out,
    input [7:0]     data_8b_in
);

    // Serializer module
    wire [7:0]       data_8b_latched;
    wire [9:0]       data_10b_encoded;
    wire [9:0]       data_10b_latched;

    latch_8bit latch_8b_inst (
        .clk(clk),
        .rst_n(rst_n),
        .data_8b_in(data_8b_in),
        .data_en(data_en),
        .data_8b_out(data_8b_latched)
    );  
    
    encoder_8b_10b encoder_inst (
        .clk(clk),
        .rst_n(rst_n),
        .data_8b_in(data_8b_latched),
        .ser_en(ser_en),
        .data_10b_out(data_10b_encoded)
    );
    
    latch_10bit latch_10b_inst (
        .clk(clk),
        .rst_n(rst_n),
        .data_10b_in(data_10b_encoded),
        .data_en(data_en),
        .data_10b_out(data_10b_latched)
    );

    piso_10bit piso_inst (
        .clk(clk),
        .rst_n(rst_n),
        .par_in(data_10b_latched),
        .load_en(ser_en),
        .ser_out(ser_out)
    );

    // Deserializer module
    wire [9:0]       data_10b;
    wire[9:0]	    data_10b_latched_d;
    wire [7:0]       data_8b_decoded;

    // Instantiate the SIPO module
    sipo_10bit sipo_inst_d (
        .clk(clk),
        .rst_n(rst_n),
        .ser_in(ser_in),
        .shift_en(par_en),
        .par_out(data_10b)
    );

    // Instantiate the 10-bit latch
    latch_10bit latch_10b_inst_d (
        .clk(clk),
        .rst_n(rst_n),
        .data_10b_in(data_10b),
        .data_en(data_en),
        .data_10b_out(data_10b_latched_d)
    );

    // Instantiate the 10b/8b decoder
    decoder_10b_8b decoder_inst_d (
        .clk(clk),
        .rst_n(rst_n),
        .data_10b_in(data_10b_latched_d),
        .par_en(par_en),
        .data_8b_out(data_8b_decoded)
    );

    // Instantiate the 8-bit latch
    latch_8bit latch_8b_inst_d (
        .clk(clk),
        .rst_n(rst_n),
        .data_8b_in(data_8b_decoded),
        .data_en(data_en),
        .data_8b_out(data_out)
    );
endmodule

module latch_8bit(
    input           clk,
    input           rst_n,
    input [7:0]     data_8b_in,
    input           data_en,
    output reg [7:0]    data_8b_out
);

    always @ ( posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            data_8b_out <= 8'h00;
        end
        else begin
            if (data_en) begin
                data_8b_out <= data_8b_in;
            end
            else data_8b_out <= data_8b_out;
        end
    end

endmodule


module encoder_8b_10b(
    input           clk,
    input           rst_n,
    input [7:0]     data_8b_in,
    input           ser_en,
    output reg[9:0]    data_10b_out
);

    reg [3:0]       temp_4b;
    reg [5:0]       temp_6b;

    always @ (posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            temp_4b <= 4'b0000;
            temp_6b <= 6'b000000;
        end
        else begin
            if (!ser_en) begin
                case (data_8b_in[7:5])
                3'b000: temp_4b <= 4'b0100;
                3'b001: temp_4b <= 4'b1001;
                3'b010: temp_4b <= 4'b0101;
                3'b011: temp_4b <= 4'b0011;
                3'b100: temp_4b <= 4'b0010;
                3'b101: temp_4b <= 4'b1010;
                3'b110: temp_4b <= 4'b0110;
                3'b111: temp_4b <= 4'b0001;
                default: temp_4b <= 4'b0000;    
                endcase
                case (data_8b_in[4:0])
                5'b00000: temp_6b <= 6'b011000;
                5'b00001: temp_6b <= 6'b011101;
                5'b00010: temp_6b <= 6'b010010;     
                5'b00011: temp_6b <= 6'b110001;
                5'b00100: temp_6b <= 6'b110101;
                5'b00101: temp_6b <= 6'b101001;
                5'b00110: temp_6b <= 6'b011001;
                5'b00111: temp_6b <= 6'b111000;
                5'b01000: temp_6b <= 6'b111001;
                5'b01001: temp_6b <= 6'b100101;
                5'b01010: temp_6b <= 6'b010101;
                5'b01011: temp_6b <= 6'b110100;
                5'b01100: temp_6b <= 6'b001101;
                5'b01101: temp_6b <= 6'b101100;
                5'b01110: temp_6b <= 6'b011100;
                5'b01111: temp_6b <= 6'b010111;
                5'b10000: temp_6b <= 6'b011011;
                5'b10001: temp_6b <= 6'b100011;
                5'b10010: temp_6b <= 6'b010011;
                5'b10011: temp_6b <= 6'b110010;
                5'b10100: temp_6b <= 6'b001011;
                5'b10101: temp_6b <= 6'b101010;
                5'b10110: temp_6b <= 6'b011010;
                5'b10111: temp_6b <= 6'b111010;
                5'b11000: temp_6b <= 6'b110011;
                5'b11001: temp_6b <= 6'b100110;
                5'b11010: temp_6b <= 6'b010110;
                5'b11011: temp_6b <= 6'b110110;
                5'b11100: temp_6b <= 6'b001110;
                5'b11101: temp_6b <= 6'b101110;
                5'b11110: temp_6b <= 6'b011110;
                5'b11111: temp_6b <= 6'b101011;
                default: temp_6b <= 6'b000000;
                endcase
            end
            else data_10b_out <= {temp_4b, temp_6b};
        end
    end 
endmodule

module latch_10bit(
    input           clk,
    input           rst_n,
    input [9:0]     data_10b_in,
    input           data_en,
    output reg [9:0]    data_10b_out
);
    always @ (posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            data_10b_out <= 10'h00;
        end
        else begin
            if (data_en) begin
                data_10b_out <= data_10b_in;
            end
            else data_10b_out <= data_10b_out;
        end
    end
endmodule

module piso_10bit(
    input           clk,
    input           rst_n,
    input [9:0]     par_in,
    input           load_en,
    output reg      ser_out
);
// >>> Module Implementation Begin

// <<< Module Implementation End
endmodule



module sipo_10bit(
    input           clk,
    input           rst_n,
    input           ser_in,
    input           shift_en,
    output reg [9:0]    par_out
);

    reg [9:0]       shift_reg;

    always @ (posedge clk)begin
        if (!rst_n) begin
            shift_reg <= 10'b0000000000;
        end
        else begin
            if (shift_en) begin
                par_out <= shift_reg;
            end
            else shift_reg <= {shift_reg[8:0], ser_in};
        end
    end

endmodule

module decoder_10b_8b(
    input           clk,
    input           rst_n,
    input [9:0]     data_10b_in,
    input           par_en,
    output reg [7:0]    data_8b_out
);

    reg [2:0]       temp_3b;
    reg [4:0]       temp_5b;

    always @ (posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            temp_3b <= 3'b000;
            temp_5b <= 5'b00000;
        end
        else begin
            if (!par_en) begin
                case (data_10b_in[9:6])
                4'b0100: temp_3b <= 3'b000;
                4'b1001: temp_3b <= 3'b001;
                4'b0101: temp_3b <= 3'b010;
                4'b0011: temp_3b <= 3'b011;
                4'b0010: temp_3b <= 3'b100;
                4'b1010: temp_3b <= 3'b101;
                4'b0110: temp_3b <= 3'b110;
                4'b0001: temp_3b <= 3'b111;
                default: temp_3b <= 3'b000;    
                endcase
                case (data_10b_in[5:0])
                6'b011000: temp_5b <= 5'b00000;
                6'b011101: temp_5b <= 5'b00001;
                6'b010010: temp_5b <= 5'b00010;     
                6'b110001: temp_5b <= 5'b00011;
                6'b110101: temp_5b <= 5'b00100;
                6'b101001: temp_5b <= 5'b00101;
                6'b011001: temp_5b <= 5'b00110;
                6'b111000: temp_5b <= 5'b00111;
                6'b111001: temp_5b <= 5'b01000;
                6'b100101: temp_5b <= 5'b01001;
                6'b010101: temp_5b <= 5'b01010;
                6'b110100: temp_5b <= 5'b01011;
                6'b001101: temp_5b <= 5'b01100;
                6'b101100: temp_5b <= 5'b01101;
                6'b011100: temp_5b <= 5'b01110;
                6'b010111: temp_5b <= 5'b01111;
                6'b011011: temp_5b <= 5'b10000;
                6'b100011: temp_5b <= 5'b10001;
                6'b010011: temp_5b <= 5'b10010;
                6'b110010: temp_5b <= 5'b10011;
                6'b001011: temp_5b <= 5'b10100;
                6'b101010: temp_5b <= 5'b10101;
                6'b011010: temp_5b <= 5'b10110;
                6'b111010: temp_5b <= 5'b10111;
                6'b110011: temp_5b <= 5'b11000;
                6'b100110: temp_5b <= 5'b11001;
                6'b010110: temp_5b <= 5'b11010;
                6'b110110: temp_5b <= 5'b11011;
                6'b001110: temp_5b <= 5'b11100;
                6'b101110: temp_5b <= 5'b11101;
                6'b011110: temp_5b <= 5'b11110;
                6'b101011: temp_5b <= 5'b11111;
                default: temp_5b <= 5'b00000;
                endcase
            end
            else data_8b_out <= {temp_3b,temp_5b};
        end
    end
endmodule


Reference solution:
rtl/generated.v: 
    reg [9:0]       shift_reg;

    always @(posedge clk) begin
        if (!rst_n) begin
            shift_reg <= 10'b0000000000;
        end 
        else begin 
            if (load_en) begin
                shift_reg <= par_in;
            end
            else begin
                ser_out <= shift_reg[0];
                shift_reg <= {1'b0, shift_reg[9:1]};  
            end
        end
    end