[GSM:3gpp] 44.006中"Address field format"相关疑问

风情123

请教下各位好心人:
最近在看44.006,遇到以下疑问:
"
6.2        Address field format
The field consists of:
        the address field extension bit EA;
        the command/response bit C/R;
        the SAPI;
        and the Link Protocol Discriminator LPD.
The format of the address field for control channels is shown in figure 4.
The address field extension bit, EA, enables extension of the field to span more than one octet. The value "0" is used to indicate an extension, the value "1" shall be used for the final address field octet.
The Link Protocol Discriminator (LPD) corresponding to the use in this Technical Specification shall take the value "0 0", all other values are reserved.
NOTE:        LPD = "0 1" corresponds to the data link protocol used for SMSCB (see 3GPP TS 44.012).
Bit        8        7        6        5        4        3        2        1
        Spare        LPD        SAPI        C/R        EA
=1

Figure 4: Address field format
"
中若EA为1可以理解,也即到此结束,即Address 的Size为1字节(即8bits)
但是若EA=0时,那么怎样判断Address到哪里结束呢?

还请大家多多指教,多谢了~