module SampleDisplay(
    output wire [6:0] display,
    output wire [3:0] digit,
    inout wire PS2_DATA,
    inout wire PS2_CLK,
    input wire rst,
    input wire clk
);
    wire reset;

    reg [7:0] scan_code, nxt_scan_code;

    wire [511:0] key_down;
    wire [8:0] last_change;
    wire been_ready;

    OnePulse one_pulse(
        .signal_single_pulse(reset),
        .signal(rst),
        .clock(clk)
    );

    SegmentController controller (
        .clk(clk),
        .rst_n(!reset),
        .signal({(last_change[8] ? 8'hE0 : 8'd0), scan_code}),
        .seg(display),
        .seg_an(digit)
    );
        
    KeyboardDecoder key_de (
        .key_down(key_down),
        .last_change(last_change),
        .key_valid(been_ready),
        .PS2_DATA(PS2_DATA),
        .PS2_CLK(PS2_CLK),
        .rst(reset),
        .clk(clk)
    );

    always @ (posedge clk, posedge reset) begin
        if (reset) begin
            scan_code <= 16'd0;
        end else begin
            scan_code <= nxt_scan_code;
        end
    end

    always @ (*) begin
        if (been_ready && key_down[last_change] == 1'b1) nxt_scan_code = last_change[7:0];
        else nxt_scan_code = scan_code;
    end
    
endmodule