DAQMX kártya példaprogram

A Form tartalma:

• Button startButton;
• Button readButton;
• TextBox inputBox;

Megjegyzés: a kártya azonosítója ("DevXX") a MAX listájában ellenőrizhető. Az alábbi kódban a "Dev1" stringet át kell írni a megfelelő értékre, amennyiben szükséges.

Tutorial program for DAQMX data acquisition card

Contents of the Form:

• Button startButton;
• Button readButton;
• TextBox inputBox;

Note: The identifier of the card ("DevXX") can be verified using MAX (Measurement and Automation Explorer). When using the following code, replace the "Dev1" string with the actual identifier of the connected device.

<syntaxhighli ght lang=csharp> using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; //Add the following references manually to the header using NationalInstruments.DAQmx; //Don't forget to add the references to the NI libraries in the project explorer as well using System.IO;

namespace DAQMX {

   public partial class Form1 : Form
   {
       //Global variables
       private Task OutTask;    //kimeneti Task: Dev1/ao0
       private AnalogSingleChannelWriter writer;  
       private Task InTask;    //bemeneti Task: Dev1/ai0
       private AnalogSingleChannelReader reader;

       double Minimumvoltage = 0;
       double Maximumvoltage = 5;
       public Form1()
       {
           InitializeComponent();
       }

       private void Form1_Load(object sender, EventArgs e)
       {
           //Read button is disabled when the program loads
           readButton.Enabled=false;
       }

//The measurement has to be initialized first //For example by using a button press

       private void startButton_Click(object sender, System.EventArgs e)
       {

//Output OutTask = new Task(); //Task constructor //Creating the output channel OutTask.AOChannels.CreateVoltageChannel("Dev1/ao0", "",

                   Minimumvoltage, Maximumvoltage,
                   AOVoltageUnits.Volts);		

writer = new AnalogSingleChannelWriter(OutTask.Stream); //Input InTask = new Task(); //Task constructor //Creating the input channel InTask.AIChannels.CreateVoltageChannel("Dev1/ai0", "",

                   AITerminalConfiguration.Differential, Minimumvoltage, Maximumvoltage,
                   AIVoltageUnits.Volts);		

reader = new AnalogSingleChannelReader(InTask.Stream);

                       //The read button is enabled after the initialization
                       readButton.Enabled=true;

}

       private void readButton_Click(object sender, System.EventArgs e)
       {
                       Double input = 0;
                       //The below function performs the writing and reading of the voltage values
                       input=write_And_Read();
                       //displaying the result
                       inputBox.Text=input.ToString("0.000");
       }
       //writing voltage (value stored in data variable)
       //and reading voltage on the input

private Double write_And_Read() { Double data=0.2; //always between 0 and 5 V! writer.WriteSingleSample(true,data);

                       //the function returns the measured voltage

return reader.ReadSingleSample(); }

       private void Form1_FormClosed(object sender, FormClosedEventArgs e)
       {
           //free up resources 

OutTask.Dispose(); InTask.Dispose();

       }

    }

} </syntaxhighlight>