always @ (posedge clk) begin

        // Increment on enable signal.
        if (en) begin
            if (x < MAX_X - 1) begin
                x <= x + 1;
            end else begin
                x <= 0;
                y <= y + 1;
            end
        end

        // Reset when no enable signal.
        if (!en) begin
             x <= 0;
             y <= 0;
        end

        // Signal done when reached max.
        // MAX_X - 2 is so that the signal is high during the last (x, y).
        if (x == MAX_X - 2 && y == MAX_Y - 1) begin
            done <= 1;
        end else begin
            done <= 0;
        end

    end