说明：  智能电表的全套IEC62056通讯协议，DLMS/COSEM通讯
(pe The DLMS/COSEM specification specifies an interface model and communication protocols for data exchange with metering equipment. The interface model provides a view of the functionality of the meter as it is available at its interface(s). It uses generic building blocks to model this functionality. The model does not cover internal, implementation-specific issues. Communication protocols define how the data can be accessed and transported. The DLMS/COSEM specification follows a three-step approach as illustrated in Figure 1: Step 1, Modelling: This covers the interface model of metering equipment and rules for data identification; Step 2, Messaging: This covers the services for mapping the interface model to protocol data units (APDU) and the encoding of this APDUs. Step 3, Transporting: This covers the transportation of the messages through the communication channel)