44. Bus Error Checker

How do you plan to solve it?

/*Write your code here*/
module error_checker_xz(input wire[7:0] bus,
                        output all_known, has_unknown,
                        output wire[7:0] bus_if_known);
    wire any_xz = (^(bus ^ bus)) === 1'bx;

    assign has_unknown = any_xz;
    assign all_known = ~any_xz;
    assign bus_if_known = {8{all_known}} & bus;  

endmodule