The OpenHarmony LiteOS Cortex-A is a new-generation kernel developed based on the Huawei LiteOS kernel. Huawei LiteOS is a lightweight operating system \(OS\) built for the Internet of Things \(IoT\) field. With the rapid development of the IoT industry, OpenHarmony LiteOS Cortex-A brings small-sized, low-power, and high-performance experience and builds a unified and open ecosystem for developers. In addition, it provides rich kernel mechanisms, more comprehensive Portable Operating System Interface \(POSIX\), and a unified driver framework, Hardware Driver Foundation \(HDF\), which offers unified access for device developers and friendly development experience for application developers. [Figure1](#fig27311582210) shows the architecture of the OpenHarmony LiteOS Cortex-A kernel.
The OpenHarmony LiteOS Cortex-A is a new-generation kernel developed based on the Huawei LiteOS kernel. Huawei LiteOS is a lightweight operating system \(OS\) built for the Internet of Things \(IoT\) field. With the rapid development of the IoT industry, OpenHarmony LiteOS Cortex-A brings small-sized, low-power, and high-performance experience and builds a unified and open ecosystem for developers. In addition, it provides rich kernel mechanisms, more comprehensive Portable Operating System Interface \(POSIX\), and a unified driver framework, Hardware Driver Foundation \(HDF\), which offers unified access for device developers and friendly development experience for application developers. [Figure1](#fig27311582210) shows the architecture of the OpenHarmony LiteOS Cortex-A kernel.
**Figure 1** Architecture of the OpenHarmony LiteOS Cortex-A kernel<aname="fig27311582210"></a>
@@ -27,7 +27,7 @@ The OpenHarmony LiteOS Cortex-A is a new-generation kernel developed based on th
├── bsd # Code of the driver and adaptation layer module related to the FreeBSD, such as the USB module
├── compat # Kernel API compatibility
│ └── posix # POSIX APIs
├── drivers # Kernel driver
├── drivers # Kernel drivers
│ └── char # Character device
│ ├── mem # Driver for accessing physical input/output (I/O) devices
│ ├── quickstart # APIs for quick start of the system
...
...
@@ -50,7 +50,7 @@ The OpenHarmony LiteOS Cortex-A is a new-generation kernel developed based on th
├── lib # Kernel library
├── net # Network module, which mainly derives from the lwIP open-source project
├── platform # Code for supporting different systems on a chip (SOCs), such as Hi3516D V300
│ ├── hw # Logic code related to clocks and interupts
│ ├── hw # Logic code related to clocks and interrupts
│ ├── include # Header files exposed externally
│ └── uart # Logic code related to the serial port
├── platform # Code for supporting different systems on a chip (SOCs), such as Hi3516D V300
...
...
@@ -67,30 +67,32 @@ The OpenHarmony LiteOS Cortex-A is a new-generation kernel developed based on th
## Usage<a name="section741617511812"></a>
OpenHarmony LiteOS Cortex-A supports the [Hi3518E V300](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/introduction-to-the-hi3518-development-board.md) and [Hi3516D V300](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/introduction-to-the-hi3516-development-board.md). You can develop and run your applications based on both development boards.
OpenHarmony LiteOS Cortex-A supports the [Hi3518E V300](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/introduction-to-the-hi3518-development-board.md) and [Hi3516D V300](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/introduction-to-the-hi3516-development-board.md). You can develop and run your applications based on both development boards.
You need to set up the compilation environment on Linux.
- For Hi3518E V300, see [Setting Up the Hi3518 Development Environment](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/setting-up-the-hi3518-development-environment.md).
- For Hi3516D V300, see [Setting Up the Hi3516 Development Environment](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/setting-up-the-hi3516-development-environment.md).
- For Hi3518E V300, see [Setting Up the Hi3518 Development Environment](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/setting-up-the-hi3518-development-environment.md).
- For Hi3516D V300, see [Setting Up the Hi3516 Development Environment](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/setting-up-the-hi3516-development-environment.md).
Download and decompress a set of source code on a Linux server to acquire the [source code](https://repo.huaweicloud.com/harmonyos/os/1.0/code-1.0.tar.gz). For more acquisition methods, see [Source Code Acquisition](https://gitee.com/openharmony/docs/blob/master/docs-en/get-code/source-code-acquisition.md).
Download and decompress a set of source code on a Linux server to acquire the [source code](https://repo.huaweicloud.com/harmonyos/os/1.0.1/code-1.0.1.tar.gz). For more acquisition methods, see [Source Code Acquisition](https://gitee.com/openharmony/docs/blob/master/en/device-dev/get-code/source-code-acquisition.md).
### Compilation and Building<a name="section2081013992812"></a>
For details about how to develop the first application, see:
-[Developing the First Example Program Running on Hi3518](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/developing-the-first-example-program-running-on-hi3518.md)
-[Developing the First Example Program Running on Hi3518](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/developing-the-first-example-program-running-on-hi3518.md)
-[Developing the First Example Program Running on Hi3516](https://gitee.com/openharmony/docs/blob/master/docs-en/quick-start/developing-the-first-example-program-running-on-hi3516.md)
-[Developing the First Example Program Running on Hi3516](https://gitee.com/openharmony/docs/blob/master/en/device-dev/quick-start/developing-the-first-example-program-running-on-hi3516.md)
-[helloworld for Hi3518EV300](https://gitee.com/openharmony/docs/blob/master/quick-start/%E5%BC%80%E5%8F%91Hi3518%E7%AC%AC%E4%B8%80%E4%B8%AA%E7%A4%BA%E4%BE%8B%E7%A8%8B%E5%BA%8F.md)；
-[helloworld for Hi3518EV300](https://gitee.com/openharmony/docs/blob/master/zh-cn/device-dev/quick-start/%E5%BC%80%E5%8F%91Hi3518%E7%AC%AC%E4%B8%80%E4%B8%AA%E7%A4%BA%E4%BE%8B%E7%A8%8B%E5%BA%8F.md)；
-[helloworld for Hi3516DV300](https://gitee.com/openharmony/docs/blob/master/quick-start/%E5%BC%80%E5%8F%91Hi3516%E7%AC%AC%E4%B8%80%E4%B8%AA%E5%BA%94%E7%94%A8%E7%A8%8B%E5%BA%8F%E7%A4%BA%E4%BE%8B.md)。
-[helloworld for Hi3516DV300](https://gitee.com/openharmony/docs/blob/master/zh-cn/device-dev/quick-start/%E5%BC%80%E5%8F%91Hi3516%E7%AC%AC%E4%B8%80%E4%B8%AA%E5%BA%94%E7%94%A8%E7%A8%8B%E5%BA%8F%E7%A4%BA%E4%BE%8B.md)。
