private void DataChannelStateTagValueChanged(Tag dataChannelStateTag, TagValueChangedEventArgs args)
{
if ((short)dataChannelStateTag.Value == (short)DataStateEnum.DataWritten)
{
try
{
_tagListener.ReadTagSynchronously(_channelToLineTag);
}
catch (PlcCommunicationException e)
{
RaiseCommunicationProblem(e);
}
if (_channelToLineTag.Value == null)
{
Thread.Sleep(50);
try
{
// try to read UDT again
_tagListener.ReadTagSynchronously(_channelToLineTag);
}
catch (PlcCommunicationException e)
{
RaiseCommunicationProblem(e);
}
if (_channelToLineTag.Value == null)
{
RaiseCommunicationProblem(new PlcCommunicationException(
"Can't listen to DataChannel " + _channelToLineTag.Name +
" because value is null for DataType " +
_channelToLineTag.DataType + " (tried it two times)",
_tagListener.AddressAndPath, ""));
}
}
if (DataReceived != null && _channelToLineTag.Value != null)
{
DataReceived(this, (TDataType)_channelToLineTag.Value);
}
try
{
_tagController.WriteTag(dataChannelStateTag, (short)DataStateEnum.DataChannelFree);
}
catch (PlcCommunicationException e)
{
RaiseCommunicationProblem(e);
}
}
}
/// <summary>
/// Callback from the Beckhoff Listener that the Datachannel changed
/// </summary>
/// <param name="dataChannelStateTag"></param>
/// <param name="args"></param>
private void DataChannelStateTagValueChanged(Tag dataChannelStateTag, TagValueChangedEventArgs args)
{
if ((short)dataChannelStateTag.Value == (short)DataStateEnum.DataWritten)
{
if (DataReceived != null)
{
int iIdx = 0;
try
{
_channelToLineTag.ClearValue();
_tagListener.ReadTagSynchronously(_channelToLineTag);
iIdx++;
}
catch (PlcCommunicationException e)
{
RaiseCommunicationProblem(e);
}
if (DataReceived != null)
{
if (_channelToLineTag.Value == null)
{
RaiseCommunicationProblem(new PlcCommunicationException("Can't listen to DataChannel " + _channelToLineTag.Name + " because value is null for DataType " + _channelToLineTag.DataType, _tagListener.AddressAndPath, ""));
}
DataReceived(this, (TDataType)_channelToLineTag.Value);
}
}
try
{
_tagController.WriteTag(dataChannelStateTag, (short)DataStateEnum.DataChannelFree);
}
catch (PlcCommunicationException e)
{
RaiseCommunicationProblem(e);
}
}
}