OpenHarmony Overview

1. Project Introduction

OpenHarmony is an open-source project incubated and operated by the OpenAtom Foundation. It aims to build a framework and platform for intelligent terminal device operating systems based on open-source methodologies, targeting the era of all-scenario, fully connected, and fully intelligent connectivity, and to foster the flourishing development of the Internet of Everything industry.

1.1 Technical Architecture

OpenHarmony follows a layered design, from bottom to top: Kernel Layer, System Service Layer, Framework Layer, and Application Layer. System functions are progressively expanded as "system > subsystem > component". In multi-device deployment scenarios, non-essential components can be pruned according to actual requirements. The OpenHarmony technical architecture is shown below.

1.1.1 Kernel Layer

Kernel Subsystem: Adopts a multi-kernel design (Linux kernel or LiteOS) so that an appropriate OS kernel can be selected for different resource-constrained devices. The Kernel Abstract Layer (KAL) shields the differences between multiple kernels and provides basic kernel capabilities to upper layers, including process/thread management, memory management, file systems, network management, and peripheral management.
Driver Subsystem: The Driver Framework (HDF) is the foundation for opening up the system hardware ecosystem, providing unified peripheral access capabilities and a driver development and management framework.

1.1.2 System Service Layer

The System Service Layer is the core capability set of OpenHarmony, providing services to applications through the Framework Layer. This layer contains the following parts:

Essential System Capability Subsystem Set: Provides the foundational capabilities for running, scheduling, and migrating distributed applications across multiple devices. It consists of subsystems such as the Distributed Soft Bus, Distributed Data Management, Distributed Task Scheduling, Common Foundation Libraries, Multi-modal Input, Graphics, Security, and AI.
Basic Software Service Subsystem Set: Provides common and universal software services, including Event Notification, Telephony, Multimedia, and DFX (Design For X).
Enhanced Software Service Subsystem Set: Provides differentiated, capability-enhancing software services tailored to different devices. It consists of subsystems such as Smart Screen dedicated services, Wearable dedicated services, and IoT dedicated services.
Hardware Service Subsystem Set: Provides hardware services, consisting of subsystems such as Location Services, User IAM, Wearable-specific hardware services, and IoT-specific hardware services.

Note

Depending on the deployment environment of different device forms, the Basic Software Service Subsystem Set, Enhanced Software Service Subsystem Set, and Hardware Service Subsystem Set can be pruned at the subsystem granularity, and each subsystem can in turn be pruned at the functional granularity.

1.1.3 Framework Layer

The Framework Layer provides multi-language user program frameworks and the Ability framework for application development (C/C++/JS), the ArkUI framework suitable for the JS language, and multi-language framework APIs that expose various software and hardware services. The APIs supported by a device vary depending on the degree of component-based tailoring of the system.

1.1.4 Application Layer

The Application Layer includes system applications and third-party non-system applications. An application consists of one or more FAs (Feature Abilities) or PAs (Particle Abilities). Among them, FAs have UI interfaces and provide the ability to interact with users; PAs have no UI interface and provide the ability to run background tasks and a unified data access abstraction. Applications developed based on FA/PA can implement specific business functions, support cross-device scheduling and distribution, and deliver a consistent and efficient application experience to users.

1.2 Technical Features

Distributed Soft Bus:

The Distributed Soft Bus is the unified foundation of multi-device terminals. It provides a unified distributed communication capability for seamless interconnection between devices, enabling fast discovery and connection of devices and efficient transmission of tasks and data.

Distributed Data Management:

Distributed Data Management is built on the Distributed Soft Bus and realizes distributed management of application data and user data. User data is no longer bound to a single physical device; business logic is separated from data storage, and data is seamlessly connected when applications run across devices, creating the foundational conditions for a consistent and smooth user experience.

Distributed Task Scheduling:

Distributed Task Scheduling builds a unified distributed service management (discovery, synchronization, registration, invocation) mechanism based on technical features such as the Distributed Soft Bus, Distributed Data Management, and Distributed Profile. It supports remote startup, remote invocation, binding/unbinding, and migration of cross-device applications, and selects the most appropriate device to run distributed tasks based on the capabilities, location, business running state, and resource usage of different devices, combined with user habits and intentions.

Device Virtualization:

The Distributed Device Virtualization platform enables resource fusion, device management, and data processing across different devices, treating surrounding devices as extensions of the phone's capabilities to jointly form a super virtual terminal.

1.2.2 Develop Once, Deploy on Multiple Devices

OpenHarmony provides the user program framework, Ability framework, and UI framework to ensure that developed applications remain consistent when running on multiple terminals. Develop once, deploy on multiple devices.

The multi-terminal software platform APIs are consistent, ensuring runtime compatibility of user programs.

Supports previewing the capability adaptation (CPU/memory/peripherals/software resources, etc.) of terminals during development.
Supports scheduling user presentation according to the compatibility between user programs and the software platform.

1.2.3 Unified OS, Elastic Deployment

Through design methods such as componentization and elastic componentization, OpenHarmony enables hardware resources to scale up or down, deploying elastically on demand across a variety of terminal devices. It comprehensively covers CPUs such as ARM, RISC-V, and x86, and RAM sizes from hundreds of KiB to the GiB level.

2. System Download Address

OpenHarmony system firmware download URL: https://ci.openharmony.cn/workbench/cicd/dailybuild/dailylist

After entering the OpenHarmony CI daily build page, select the branch OpenHarmony-5.0.3-Release as shown in the figure.

Find the version whose pipeline name is dayu200_5.0.3-Release and click the download link as shown in the figure.

Select the download link next to the image package to download the dayu200_5.0.3-Release firmware.

Note

dayu200_5.0.3-Release is a 32-bit system. For a 64-bit system, please select dayu200-arm64_5.0.3-Release.

Reference

For details, please refer to: https://docs.openharmony.cn/pages/v5.0/zh-cn/OpenHarmony-Overview_zh.md/