# XTS - [Introduction](#section465982318513) - [System Types](#section125090457443) - [Directory Structure](#section161941989596) - [Constraints](#section119744591305) - [Usage Guidelines](#section137768191623) - [Test Case Development Guidelines](#section3695134065513) - [C-based Test Case Development and Compilation \(for the Mini System\)](#section198193336544) - [C-based Test Case Execution \(for the Mini System\)](#section13820233175418) - [C++-based Test Case Development and Compilation \(for Standard and Small Systems\)](#section3822123311540) - [C++-based Test Case Execution \(for Standard and Small Systems\)](#section128222336544) ## Introduction The X test suite \(XTS\) subsystem contains a set of OpenHarmony certification test suites, including the currently supported distributed compatibility test suite \(DCTS\). This subsystem contains the DCTS and **tools** software package. - The **dcts** directory stores the source code and configuration files of DCTS test cases. The DCTS helps device vendors detect the distributed scenario incompatibility as early as possible and ensures that the software is compatible to OpenHarmony during the entire development process. - The **tools** software package stores the test case development framework related to **dcts**. ## System Types OpenHarmony supports the following system types: - Mini system A mini system runs on the devices whose memory is greater than or equal to 128 KiB and that are equipped with MCU processors such as ARM Cortex-M and 32-bit RISC-V. This system provides multiple lightweight network protocols and graphics frameworks, and a wide range of read/write components for the IoT bus. Typical products include connection modules, sensors, and wearables for smart home. - Small system A small system runs on the devices whose memory is greater than or equal to 1 MiB and that are equipped with application processors such as ARM Cortex-A. This system provides higher security capabilities, standard graphics frameworks, and video encoding and decoding capabilities. Typical products include smart home IP cameras, electronic cat eyes, and routers, and event data recorders \(EDRs\) for smart travel. - Standard system A standard system runs on the devices whose memory is greater than or equal to 128 MiB and that are equipped with application processors such as ARM Cortex-A. This system provides a complete application framework supporting the enhanced interaction, 3D GPU, hardware composer, diverse components, and rich animations. This system applies to high-end refrigerator displays. ## Directory Structure ``` /test/xts ├── dcts # Test code │ └── subsystem # Source code of subsystem test cases for the standard system │ └── subsystem_lite # Source code of subsystems test cases for mini and small systems │ └── common # Source code of Test cases rely on shared memory for mini and small systems │ └── BUILD.gn # Build configuration of test cases for the standard system │ └── build_lite │ └── BUILD.gn # Build configuration of test cases for mini and small systems └── tools # Test tool code ``` ## Constraints Test cases for the mini system must be developed based on C, and those for the small system must be developed based on C++. ## Usage Guidelines **Table 1** Test case levels