OscilloscopeStream.cpp

/**
 * OscilloscopeStream.cpp - for LibTiePie 0.5+
 *
 * This example performs a stream mode measurement and writes the data to OscilloscopeStream.csv.
 *
 * Find more information on http://www.tiepie.com/LibTiePie .
 */

#include 
#include 
#include "libtiepie++.h"
#include "PrintInfo.h"

#if defined(__linux) || defined(__unix)
  #include 
  #include 
#endif

using namespace std;
using namespace LibTiePie;

int main()
{
  int status = EXIT_SUCCESS;

  // Initialize library:
  Library::init();

  // Print library information:
  printLibraryInfo();

  // Update device list:
  DeviceList::update();

  // Try to open an oscilloscope with with stream measurement support:
  Oscilloscope* scp = 0;

  for(uint32_t index = 0; index < DeviceList::count(); index++)
  {
    DeviceListItem* item = DeviceList::getItemByIndex(index);

    if(item->canOpen(DEVICETYPE_OSCILLOSCOPE) && (scp = item->openOscilloscope()))
    {
      // Check for stream measurement support:
      if(!(scp->measureModes() & MM_STREAM))
      {
        delete scp;
        scp = 0;
      }
    }

    delete item;

    if(scp)
    {
      break;
    }
  }

  if(scp)
  {
    float** channelData = 0;
    uint16_t channelCount = 0;

    try
    {
      // Get the number of channels:
      channelCount = scp->channels.count();

      // Set measure mode:
      scp->setMeasureMode(MM_STREAM);

      // Set sample frequency:
      scp->setSampleFrequency(1e3); // 1 kHz

      // Set record length:
      scp->setRecordLength(1000); // 1 kS
      const uint64_t recordlength = scp->recordLength(); // Read actual record length

      // For all channels:
      for(uint16_t ch = 0; ch < channelCount; ch++)
      {
        OscilloscopeChannel& channel = scp->channels[ch];

        // Enable channel to measure it:
        channel.setEnabled(true);

        // Set range:
        channel.setRange(8); // 8 V

        // Set coupling:
        channel.setCoupling(CK_DCV); // DC Volt
      }

      // Print oscilloscope info:
      printDeviceInfo(scp);

      // Create data buffers:
      channelData = new float*[channelCount];
      for(uint16_t ch = 0; ch < channelCount; ch++)
      {
        channelData[ch] = new float[recordlength];
      }

      // Open file with write/update permissions:
      const std::string filename("OscilloscopeStream.csv");
      ofstream csv(filename.c_str() , std::ofstream::out);

      if(csv.is_open())
      {
        // Start measurement:
        scp->start();

        // Write csv header:
        csv << "Sample";
        for(uint16_t ch = 0; ch < channelCount; ch++)
        {
          csv << ";Ch" << (ch + 1);
        }
        csv << endl;

        uint64_t currentSample = 0;

        for(uint8_t chunk = 0; chunk < 10; chunk++) // Measure 10 chunks
        {
          // Print a message, to inform the user that we still do something:
          cout << "Data chunk " << (chunk + 1) << endl;

          // Wait for measurement to complete:
          while(!(scp->isDataReady() || scp->isDataOverflow()))
          {
            // 10 ms delay, to save CPU time:
#if defined(_WIN32) || defined(_WIN64)
            Sleep(10);
#elif defined(__linux) || defined(__unix)
            usleep(10000);
#endif
          }

          // Throw error on data overflow:
          if(scp->isDataOverflow())
          {
            throw std::runtime_error("Data overflow!");
          }

          // Get data:
          uint64_t samplesRead = scp->getData(channelData , channelCount , 0 , recordlength);

          // Write the data to csv:
          for(uint64_t i = 0; i < samplesRead; i++)
          {
            csv << currentSample + i;
            for(uint16_t ch = 0;  ch < channelCount; ch++)
            {
              csv << ";" << (float)channelData[ch][i];
            }
            csv << endl;
          }

          currentSample += samplesRead;
        }

        cout << "Data written to: " << filename << endl;

        // Close file:
        csv.close();

        // Stop measurement:
        scp->stop();
      }
      else
      {
        cerr << "Couldn't open file: " << filename;
        status = EXIT_FAILURE;
      }
    }
    catch(const exception& e)
    {
      cerr << "Exception: " << e.what() << endl;
      status = EXIT_FAILURE;
    }

    // Delete data buffer:
    if(channelData)
      for(uint16_t ch = 0; ch < channelCount; ch++)
        delete [] channelData[ch];
    delete [] channelData;

    // Close oscilloscope:
    delete scp;
  }
  else
  {
    cerr << "No oscilloscope available with stream measurement support!" << endl;
    status = EXIT_FAILURE;
  }

  // Exit library:
  Library::exit();

  return status;
}