Packets
Each packet consists of 3 entities, the access code (68/72 bits), the header (54 bits) , and the payload (0-2745 bits).
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Access Code: Access code are used for timing synchronization, offset compensation, paging and inquiry. There are three different types of Access code: Channel Access Code (CAC), Device Access Code (DAC) and Inquiry Access Code (IAC). The channel access code identifies a unique piconet while the DAC is used for paging and its responses. IAC is used for inquiry purpose.
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Header: The header contains information for packet acknowledgement, packet numbering for out-of-order packet reordering, flow control, slave address and error check for header.
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Payload: The packet payload can contain either voice field, data field or both. It it has a data field, the payload will also contain a payload header.
