change mac in u-boot

Any one knows how to change those values (the ones with ÿÿÿÿÿÿÿÿÿÿÿÿ) and how to change the mac address.

Anyone with serial cable can tell me the right values.

ar7100> board_model_id_showboard_model_id : WNDR3800

ar7100> flinfo
Bank # 1: The hell do you want flinfo for??

ar7100> board_hw_id_setboard_hw_id_set         - set board_hw_id
ar7100> board_hw_id_showboard_hw_id : 29763654+16+128

ar7100> board_passphrase_showboard_passphrase : ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ

ar7100> board_ssid_showboard_ssid : ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ

ar7100>

ar7100> dnishow

eth0   mac: ff:ff:ff:ff:ff:ff

eth1   mac: ff:ff:ff:ff:ff:ff

wlan5g mac: ff:ff:ff:ff:ff:ff

wpspin    : ÿÿÿÿÿÿÿÿ

sn        : ÿÿÿÿÿÿÿÿÿÿÿÿÿ

ar7100>

ar7100> macshow

lan mac: ff:ff:ff:ff:ff:ff

wan mac: ff:ff:ff:ff:ff:ff

wlan5g mac: ff:ff:ff:ff:ff:ff

Thanks.