time:
  - platform: host
    id: esptime
    timezone: Australia/Sydney

logger:
  level: VERBOSE

host:
  mac_address: "62:23:45:AF:B3:DD"

esphome:
  on_boot:
    - lambda: |-
        static const uint8_t my_addr[6] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
        if (!mac_address_is_valid(my_addr))
          ESP_LOGD("test", "Invalid mac address %X", my_addr[0]); // etc.