CTL_STATUS_t ctl_net_search_for_first_phy(CTL_NET_INTERFACE_t *net);
ctl_net_search_for_first_phy tries to read the PHY identification registers from each PHY on the MAC interface net, starting at address zero and progressing through address 31. If a PHY is found, ctl_net_search_for_first_phy returns the address corresponding to that PHY and the PHY address is set in the network interface's PHY driver. If no PHY is found, ctl_net_search_for_first_phy returns CTL_PHY_NOT_FOUND.
ctl_net_search_for_first_phy returns a standard status code.