MAX_PHY_CONFIG
if (set_root_node < 0 || set_root_node > MAX_PHY_CONFIG)
if (set_gap_count < 0 || set_gap_count > MAX_PHY_CONFIG)
if ( (send_link_on < 0) || (send_link_on > MAX_PHY_CONFIG) )
if ( (send_reset_start < 0) || (send_reset_start > MAX_PHY_CONFIG) )