讲解zigbee协议规范比较好的书，主要有物理层，网络层，MAC的讲解-Explain zigbee agreement standard good books, basically have the physical layer, network layer, the MAC s explanation

Mac层帧结构。介质访问控制层(MAC)帧被称为MAC协议数据单元(MPDU)，其长度不超过127个字节。它具有四种不同的帧形式，即信标帧、数据帧、确认帧和命令帧。-Mac layer frame structure. MAC layer (MAC) frame is called MAC Protocol Data Unit (MPDU), whose length does not exceed 127 bytes. It has four different forms of frames