I am using PCI-6221 and DAQmx 8.7.2 and C# for programming
I want to write digital ports first, and after it completes, it will get a single sample analog input.
Here is my program.
Can anyone point out the problem ? Because I used step-by-step debug, the AnalogSingleSampleRead() is not executed.
///////////////////////////////////////////////////////////////////
namespace NItest {
public partial class Form1 : Form
{
//global variables
private double data; private Task digitalWriteTask = new Task();
private Task AnalogTask = new Task(); private DigitalMultiChannelWriter ThreePortsWriter; private AnalogSingleChannelReader myAnalogReader;
byte[,] DOutputss = new byte[3, 8];
public Form1() {
InitializeComponent();
initNI();
}
private void initNI() {
digitalWriteTask.DOChannels.CreateChannel(Port0, "", ChannelLineGrouping.OneChannelForAllLines);
digitalWriteTask.DOChannels.CreateChannel(Port1, "", ChannelLineGrouping.OneChannelForAllLines); digitalWriteTask.DOChannels.CreateChannel(Port2, "", ChannelLineGrouping.OneChannelForAllLines);
digitalWriteTask.Control(TaskAction.Verify);
ThreePortsWriter = new DigitalMultiChannelWriter(digitalWriteTask.Stream); digitalWriteTask.Start();
AnalogTask.AIChannels.CreateVoltageChannel("Dev1/ai0", "", AITerminalConfiguration.Rse, 0, 5, AIVoltageUnits.Volts); AnalogTask.Control(TaskAction.Verify);
myAnalogReader = new AnalogSingleChannelReader(AnalogTask.Stream); AnalogTask.Start();
ThreePortsWriter.SynchronizeCallbacks = true; }//end of iniNI
private void DAQmxAsyncWrite() {
//[give some value to DOutputss]
IAsyncResult handle=ThreePortsWriter.BeginWriteMultiSamplePort(false, DOutputss, new AsyncCallback(myCallback), null);
}
private void myCallback(IAsyncResult ar) {
ThreePortsWriter.EndWrite(ar);
data = myAnalogReader.ReadSingleSample();
}
}
}
////////////////////////////////////////////////////////////////////
When I call DAQmxAsyncWrite(), the program never execute myCallback().
Why please?
Thank you all.
Message Edited by timinmanchester on 11-29-2008 08:48 AM
Message Edited by timinmanchester on 11-29-2008 08:49 AM
Message Edited by timinmanchester on 11-29-2008 08:51 AM
