44. Bus Error Checker

How do you plan to solve it?

module error_checker_xz (
    input  [7:0] bus,
    output       all_known,
    output       has_unknown,
    output [7:0] bus_if_known
);
    // TODO: implement both comparisons
    assign has_unknown  = (^(bus ^ bus)) === 1'bx;
    assign all_known    = ~has_unknown;
    assign bus_if_known = (all_known) ? bus : 8'h00;
endmodule