蓝牙概述

蓝牙基础架构

蓝牙分为 BT Host、HCI (Host Controller Interface) 和 BT Controller 三部分:

模块		描述
BT Host	Application	包含蓝牙 APIs，以及由此实现的 Peripheral、Central、Scatternet、Mesh、A2DP、LE Audio 等应用
	Framework	包含以下 lib： LE audio lib：\component\bluetooth\rtk_stack\platform\amebaxxx\lib\(km4\kr4\ca32)\leaudio.a BLE mgr lib：\component\bluetooth\rtk_stack\platform\amebaxxx\lib\(km4\kr4\ca32)\ble_mgr.a BT mgr lib：\component\bluetooth\rtk_stack\platform\amebaxxx\lib\(km4\kr4\ca32)\bt_mgr.a system lib：\component\bluetooth\rtk_stack\platform\amebaxxx\lib\(km4\kr4\ca32)\sysm.a 各 lib 的作用： LE audio lib & BLE mgr lib：实现了 BAP 和 CAP，以及 LE audio 依赖的 BLE profile BT mgr lib：实现了 BR/EDR profile system lib：提供一些系统相关的功能
	Host stack	lib 路径：\component\bluetooth\rtk_stack\platform\amebaxxx\lib\(km4\kr4\ca32)\(ble_only\dual_mode)\btgap.a 实现了蓝牙上层协议栈的功能，包括 GAP、GATT、L2CAP、ATT 和 SMP 等
HCI		Controller 与 Host 唯一的通信接口，两者之间的所有数据交互都通过该接口完成
BT Controller		lib 路径：\component\bluetooth\driver\platform\amebaxxx\hci\bt_normal_patch.c 以二进制数组形式提供，实现了蓝牙下层协议栈的功能，包括 Link Layer 和 PHY

蓝牙的基础架构如下图所示：

蓝牙功能支持列表

RTL8721DxRTL8720ERTL8710ERTL8726ERTL8713ERTL8730ERTL8721F

Item	Feature	Supported
Physical	BR/EDR
	BLE
BLE 4.0	Advertiser
	Scanner
	Initiator
	Master
	Slave
	Link Layer Encryption
	BLE Max. Link (Theoretical value)	8 Master + 3 Slave
BLE 4.1	Low Duty Cycle Directed Advertising
	MWS Coexistence
	LE Ping
	LE Link Layer Topology
	LE Scatternet
BLE 4.2	LE Data Length Extension
	LE Secure Connection
	Link Layer Privacy
	Link Layer Extended Scanner Filter Policies
BLE 5.0	LE 2Mbps PHY
	LE Long Range
	LE Advertising Extensions
	LE Channel Selection Algorithm #2
	High Duty Cycle Non-Connectable Advertising
	LE Periodic Advertising

蓝牙功能配置

功能	配置文件	配置项
Link Layer Privacy	以 Peripheral 为例： \component\bluetooth\example\ble_peripheral\peripheral.c	修改 privacy_enable 为 true
LE Advertising Extensions	\component\bluetooth\api\include\bt_api_config.h	修改 RTK_BLE_5_0_AE_ADV_SUPPORT 和 RTK_BLE_5_0_AE_SCAN_SUPPORT 为 1
LE Periodic Advertising	\component\bluetooth\api\include\bt_api_config.h	修改相应 SoC 的 RTK_BLE_5_0_AE_ADV_SUPPORT，RTK_BLE_5_0_AE_SCAN_SUPPORT，RTK_BLE_5_0_PA_ADV_SUPPORT 和 RTK_BLE_5_0_PA_SYNC_SUPPORT 为 1
Periodic Advertising Sync Transfer (PAST)	\component\bluetooth\api\include\bt_api_config.h	修改相应 SoC 的 RTK_BLE_5_0_AE_ADV_SUPPORT，RTK_BLE_5_0_AE_SCAN_SUPPORT，RTK_BLE_5_0_PA_ADV_SUPPORT，RTK_BLE_5_0_PA_SYNC_SUPPORT， RTK_BLE_5_1_PAST_SENDER_SUPPORT 和 RTK_BLE_5_1_PAST_RECIPIENT_SUPPORT 为 1
SMP OOB	\component\bluetooth\api\include\bt_api_config.h	默认开启，修改 RTK_BLE_SMP_OOB_SUPPORT 为 0 关闭
LE Data Length Extension	\component\bluetooth\api\include\bt_api_config.h	默认开启，修改 RTK_BLE_4_2_DATA_LEN_EXT_SUPPORT 为 0 关闭
SET PHYS	\component\bluetooth\api\include\bt_api_config.h	默认开启，修改 RTK_BLE_5_0_SET_PHYS_SUPPORT 为 0 关闭
LE Power Control	\component\bluetooth\api\include\bt_api_config.h	修改 RTK_BLE_5_2_POWER_CONTROL_SUPPORT 为 1
EATT	\component\bluetooth\api\include\bt_api_config.h	修改 RTK_BT_5_2_EATT_SUPPORT 为 1