module error_checker_xz (
input [7:0] bus,
output all_known,
output has_unknown,
output [7:0] bus_if_known
);
wire parity = ^bus;
assign all_known = (parity === 1'b0 || parity === 1'b1);
assign has_unknown = ~all_known;
assign bus_if_known = all_known ? bus : 8'h00;
endmodule