說明：如下文章內容源於Core 4.2
The format of Advertising data and Scan Response data is shown in Figure 11.1. The data consists of a significant part and a non-significant part. The significant part contains a sequence of AD structures. Each AD structure shall have a Length field of one octet, which contains the Length value, and a Data field of Length octets. The first octet of the Data field contains the AD type field.
The content of the remaining Length - 1 octet in the Data field depends on the value of the AD type field and is called the AD data. The non-significant part extends the Advertising and Scan Response data to 31 octets and shall contain all-zero octets.
If the Length field is set to zero, then the Data field has zero octets. This shall only occur to allow an early termination of the Advertising or Scan Response data.
Only the significant part of the Advertising or Scan Response data needs to be sent over the air.
The Advertising and Scan Response data is sent in advertising events. The Advertising Data is placed in the AdvData field of ADV_IND, ADV_NONCONN_IND, and ADV_SCAN_IND packets. The Scan Response data is sent in the ScanRspData field of SCAN_RSP packets.
The AD type data formats and meanings are defined in [Core Specification Supplement], Part A. The AD type identifier values are defined in the Assigned Numbers document.
https://www.bluetooth.com/specifications/assigned-numbers/
https://www.bluetooth.com/specifications/assigned-numbers/generic-access-profile/