Setting up (C++)

To start working with openDAQ™, the requisite binaries are required. They can be obtained at the openDAQ™ documentation and releases webpage. The binaries are currently available for Windows and Ubuntu (20.04 or newer).

  • Windows

  • Linux

To install openDAQ™, download the opendaq-3.20-win64.exe installer, run it, and follow its instructions. Make sure to add openDAQ™ to the system path to be able to run openDAQ™ application examples.

We recommend using the default installation path to avoid issues requiring additional environment variable modifications and troubleshooting.

To install openDAQ™ on Ubuntu 20.04 or newer, download the opendaq-3.20-ubuntu20.04-x86_64.deb Debian package. Install it using the following command:

sudo apt install ./opendaq-{version}-ubuntu20.04-x86_64.deb

Creating an openDAQ™ project

We start our project from the "quick_start_app" example that can be found at the openDAQ™ documentation and releases webpage. Download the examples.zip archive and extract it to a folder of choice.

Requirements

  • Windows

  • Linux

  • CMake (3.20 or newer)

  • CMake generator and C++ compiler (Visual Studio 2022 is recommended)

  • CMake (3.20 or newer)

  • CMake generator and C++ compiler (g++ is recommended)

Run sudo apt install cmake build-essential to install the required build tools.

Building the project

To build the project, navigate to the cpp/quick_start directory and enter the following command into a terminal or command prompt instance:

cmake -DCMAKE_BUILD_TYPE=Release -Bbuild .

With this, we are ready to start developing. We fill in our quick_start_empty.cpp executable code as follows:

#include <opendaq/opendaq.h>
#include <iostream>
#include <thread>

int main(int argc, const char* argv[])
{
    // Create a fresh openDAQ(TM) instance, which acts as the entry point into our application
    daq::InstancePtr instance = daq::Instance(MODULE_PATH);

    std::cout << "Press \"enter\" to exit the application..." << std::endl;
    std::cin.get();
    return 0;
}

When creating the openDAQ™ instance, we need to specify the root directory of our openDAQ™ Modules. Conveniently, the CMake configuration pre-filled the correct directory into the MODULE_PATH macro definition.

We now compile and run our program.

  • Windows

  • Linux

cd build
cmake --build . --config Release
cd Release
.\quick_start_empty.exe
cd build
cmake --build .
./quick_start_empty

If you managed to reach this point, you have successfully created your first openDAQ™ project! To find out more about using openDAQ™ applications to connect to, configure, and read data of Devices, continue with the openDAQ™ application quick start guide.

Troubleshooting

  • Windows

  • Linux

  1. If, when running a CMake command, the following error is displayed: "`cmake` is not recognized as an internal or external command, operable program or batch file.", make sure that CMake is added to the PATH environment variable.

  2. If openDAQ™ is not found when running CMake, create a new environment variable named openDAQ_ROOT, with its value being the directory where openDAQ™ is installed.

  3. If the .dll shared libraries are not found when running the above example, add the openDAQ/bin folder path to the PATH environment variable. The bin folder is located within the openDAQ™ installation folder.

  4. If no devices are found when discovering devices, check the MODULE_PATH variable if it points to the folder where modules are located. This is usually c:\Program Files\openDAQ\bin\modules. If not, replace the MODULE_PATH with folder string.

  1. If the cmake command is not found, make sure that the cmake executable is located in a folder that is included in your PATH environment variable.

  2. If openDAQ™ is not found when running CMake, export the openDAQ_ROOT variable to point at /opt/opendaq (export openDAQ_ROOT=/opt/opendaq).

  3. If the .so shared libraries are not found when running the above example, add /opt/opendaq/lib to the LD_LIBRARY_PATH environment variable (export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/opendaq/lib)

  4. If no devices are found when discovering devices, check the MODULE_PATH variable if it points to the folder where modules are located. This is usually opt/opendaq/lib/modules. If not, replace the MODULE_PATH with folder string.