SDK Introduction

Overview

The SDK consists of the following three parts:

SDK
  ├── component                   Components such as FreeRTOS, SoC, mbed API, Wi-Fi, network, etc.
  ├── tools                       Tools
  └── cmake                       Compilation abstraction layer

component

This directory contains the core functional components of the SDK, which are called by upper-layer applications. Common components are listed in the following table:

Item	Description
at_cmd	AT command support module
audio	Audio codec driver, supports: alc5616/alc5640/alc5651/alc5660/alc5679/alc5680/sgtl5000
bluetooth	Bluetooth protocol stack source code and related library files
example	application examples, including:atcmd_host,network,ota,usb,peripherals, etc.
file_system	File system implementation, includes: fatfs, littlefs, ftl, kv, vfs, etc.
lwip	LWIP protocol stack APIs and source code
network	Network protocol support, includes: cJSON CoAP DHCP HTTP/2 HTTP Client (httpc) HTTP Server (httpd) mDNS MQTT Ping iPerf SNTP WebSocket XML
os	FreeRTOS real-time operating system source code and OS APIs wrapper layer implementation
soc	SoC-related core modules, includes: app: System monitoring and Shell tools loader: Bootloader and GDB Loader cmsis: Arm header files defining CPU registers and basic operation APIs cmsis-dsp: Arm CMSIS-DSP digital signal processing library fwlib: Low-level drivers such as Audio Codec, SPORTS, UART, I2C, SPI, Timer, PWM, etc. img3: Trustzone support (may not be enabled) hal: Mbed APIs encapsulated based on Raw APIs main: main program entry misc: Other miscellaneous functions such as crashdump, OTA, PMU, etc. project: entry of build and configure swlib: Standard software library functions provided by ROM, such as _memcpy, _memcmp, etc. usrcfg: User-defined configuration files
ssl	Secure communication protocol stack, implemented based on mbed TLS
usb	USB class drivers and verification code
utils	Utility modules, includes: IPC (Inter-Processor Communication) Ringbuffer Unit Test Framework
wifi	Wi-Fi functional module, provides the following interfaces: Wi-Fi NIC mode: Used as a traditional Wi-Fi card R-mesh: Realtek Wi-Fi Mesh CSI: Wi-Fi sensing KVR: Wi-Fi roaming WPS: Wi-Fi Protected Setup MCC: Wi-Fi multi-channel coexistence Promisc: Wi-Fi promiscuous mode, capable of receiving all packets on current channel Fast connect: Rapid connection after Wi-Fi restart

Under the soc directory, each SoC has a main subdirectory, which serves as the main program entry point for that SoC. As an SoC may contain multiple MCUs, each MCU is assigned its own independent subdirectory.

component/soc/xxx/main
  ├── {mcu1}/                           Private main program directory for each MCU
  └── {mcu2}/                           Private main program directory for each MCU
     ├── inc/                           Header files (e.g., ``FreeRTOSConfig.h``, ``build_info.h``)
     └── src/                           Main program source code

Under the soc directory, each SoC has a project subdirectory, including Kconfig, CMake and layout files, which serves as the compilation entry point for that SoC. For each MCU within the SoC, there is a corresponding project_xx subdirectory containing linker scripts, as well as CMake configuration files for building the Bootloader and Application Image.

component/soc/xxx/project
  ├── project_{mcu1}/                   Private configuration directory for each MCU
  └── project_{mcu2}/                   Private configuration directory for each MCU; there will be multiple directories if the SoC contains multiple MCUs
     ├── ld/                            Linker scripts
     ├── lib/                           Library files
     └── make/                          CMake scripts used for compiling images

tools

This directory contains tools required during IC development.

Item	Description
TraceTool	Used for printing logs and sending commands Trace Tool
ImageTool	Used for downloading firmware Image Tool
DownloadServer	Socket-based OTA server program
DownloadServer (HTTP)	HTTP-based OTA server program
iperf	Used for Wi-Fi throughput testing
littlefs	Generates the littlefs file system
meta_tools	VS Code extension SDK-side adaptation toolset

Critical Header Files

The following table lists some key header files in the SDK and their descriptions:

Item	Description	Location
basic_types.h	RTK_SUCCESS/RTK_FAIL TRUE/FALSE ENABLE/DISABLE ON/OFF NULL u8/u16/u32/u64 BOOL BIT x …	component/soc/amebaxxx/fwlib/include
section_config.h	Definitions of various sections in the linker script: BOOT_RAM_DATA_SECTION IMAGE2_RAM_TEXT_SECTION …
ameba_soc.h	Provides Raw APIs for low-level drivers (recommended to use) Compared to mbed APIs, Raw APIs offer more flexible, rich, and efficient hardware configuration interfaces
mbed API headers	High-level encapsulation interfaces based on Raw APIs, providing relatively simplified functionality	component/soc/amebaxxx/hal