> ## Documentation Index > Fetch the complete documentation index at: https://dragonwingdocs.qualcomm.com/llms.txt > Use this file to discover all available pages before exploring further. # Develop a sample ROS2 application This information describes how to use the QIR SDK toolchain to compile a simple ROS 2 sample application. The demos and code for both Python and C++ development are available as examples. ## Install the prebuilt `QIR SDK `to the host computer On the host computer, go to the artifacts directory and decompress `QIR SDK` using the `tar` command: ```xml theme={null} cd /target/qcs9075-iq-9075-evk/qirpsdk_artifacts/qcs9075-iq-9075-evk tar -zxvf qirp-sdk_.tar.gz ``` This command generates the `qirp-sdk` directory. **Note** * The `qirp-sdk_.tar.gz` is located in the deployed path of QIR artifacts. The `` changes with each release, such as 2.0.0, 2.0.1. For example, the complete package name can be `qirp-sdk_2.7.0.tar.gz`. * For all released versions, see [Qualcomm® Intelligent Robotics SDK (QIR SDK) 2.0 Release Notes](../../Key-Documents/QIR-SDK-Release-Notes/). * The QIR SDK supports these development kits for Qualcomm Linux: | **Development kit** | **Machine name** | | :------------------------------------------: | :--------------: | | Qualcomm DragonwingTM IQ-9075 EVK | `iq-9075-evk` | | Qualcomm DragonwingTM IQ-8275 EVK | `iq-8275-evk` | ## Using QIR SDK to develop applications 1. Set up the cross-compile environment. ```powershell theme={null} cd /target/qcs9075-iq-9075-evk/qirpsdk_artifacts/qcs9075-iq-9075-evk/qirp-sdk source setup.sh ``` 2. Fetch the project as the code baseline. ```cpp theme={null} git clone https://github.com/ros2/demos.git -b jazzy ``` 3. Develop your own application either in C++ or Python. 1. Develop your own C++ application. The following is an example. ```powershell theme={null} cd demos/demo_nodes_cpp vim src/topics/talker.cpp +46 ``` Change the `demo_nodes_cpp/src/topics/talker.cpp` msg data in line `46`: ```powershell theme={null} msg_->data = "Hello World : Qualcomm : " + std::to_string(count_++); ``` 2. Set the necessary environment variables and use the colcon tool to build the ROS2 package demo\_nodes\_cpp and its dependencies. ```powershell theme={null} colcon build --merge-install --packages-up-to demo_nodes_cpp --cmake-args ${CMAKE_ARGS} ``` 3. Push the demo to the device. ```powershell theme={null} cd demo_nodes_cpp/install tar -czvf demo_nodes_cpp.tar.gz lib share scp demo_nodes_cpp.tar.gz root@[ip-addr]:/opt/ ssh root@[ip-addr] (ssh) mount -o remount,rw /usr (ssh) tar --no-overwrite-dir --no-same-owner -zxf /opt/demo_nodes_cpp.tar.gz -C /usr/ ``` 4. Run the demo application on the device. i. On the first terminal, run these commands: ```shell theme={null} (ssh) source /usr/share/qirp-setup.sh (ssh) ros2 run demo_nodes_cpp talker ``` ii. On the second terminal, run these commands: ```shell theme={null} (ssh) source /usr/share/qirp-setup.sh (ssh) ros2 run demo_nodes_cpp listener ``` 5. Check the output. Terminal 1 output: ```shell theme={null} [INFO] [1739864779.759719598] [talker]: Publishing: 'Hello World : Qualcomm : 1' [INFO] [1739864780.759687179] [talker]: Publishing: 'Hello World : Qualcomm : 2' [INFO] [1739864781.760812014] [talker]: Publishing: 'Hello World : Qualcomm : 3' ... ``` Terminal 2 output: ```shell theme={null} [INFO] [1739864779.760348380] [listener]: I heard: [Hello World : Qualcomm : 1] [INFO] [1739864780.760276535] [listener]: I heard: [Hello World : Qualcomm : 2] [INFO] [1739864781.762066296] [listener]: I heard: [Hello World : Qualcomm : 3] ... ``` 1. Develop your own Python application. The following is an example. ```powershell theme={null} cd demos/demo_nodes_py vim demo_nodes_py/topics/talker.py +33 ``` Change the `demo_nodes_py/topics/talker.py` msg data in line `33`: ```powershell theme={null} msg.data = 'Hello World : Qualcomm : {0}'.format(self.i) ``` 2. Set the necessary environment variables and use the colcon tool to build the ROS 2 package demo\_nodes\_py and its dependencies. ```powershell theme={null} colcon build --merge-install --packages-up-to demo_nodes_py ``` 3. Push the demo to the device. ```powershell theme={null} cd demo_nodes_py/install tar -czvf demo_nodes_py.tar.gz lib share scp demo_nodes_py.tar.gz root@[ip-addr]:/opt/ ssh root@[ip-addr] (ssh) mount -o remount,rw /usr (ssh) tar --no-overwrite-dir --no-same-owner -zxf /opt/demo_nodes_py.tar.gz -C /usr/ ``` 4. Run the demo application on the device. i. On the first terminal, run these commands: ```shell theme={null} (ssh) export HOME=/home (ssh) source /usr/bin/ros_setup.sh && source /usr/share/qirp-setup.sh (ssh) ros2 run demo_nodes_py talker ``` ii. On the second terminal, run these commands: ```shell theme={null} (ssh) export HOME=/home (ssh) source /usr/bin/ros_setup.sh && source /usr/share/qirp-setup.sh (ssh) ros2 run demo_nodes_py listener ``` 5. Check the output. Terminal 1 output: ```shell theme={null} [INFO] [1739864779.759719598] [talker]: Publishing: 'Hello World : Qualcomm : 1' [INFO] [1739864780.759687179] [talker]: Publishing: 'Hello World : Qualcomm : 2' [INFO] [1739864781.760812014] [talker]: Publishing: 'Hello World : Qualcomm : 3' ... ``` Terminal 2 output: ```shell theme={null} [INFO] [1739864779.760348380] [listener]: I heard: [Hello World : Qualcomm : 1] [INFO] [1739864780.760276535] [listener]: I heard: [Hello World : Qualcomm : 2] [INFO] [1739864781.762066296] [listener]: I heard: [Hello World : Qualcomm : 3] ... ```