原文:A Smart Battery that complies with this specification must support all the
command codes contained in this specification. It must support the defaults as
specified. Additionally, it must support all modes and functions specified
except those which it can explicitly signal the presence or absence thereof.
想請問，it can explicitly signal the presence or absence thereof這句話怎麼翻譯?

試翻：它能明白指出有或沒有支援的 modes 與 functions