private void EveryNCallback()
{
var dict = new Dictionary <INidaqSessionTask, NILoop.HandleInfo>();
foreach (var task in _tasks.OfType <NidaqSessionAnalogIn>().Where(t => t.Nodes.Count > 0))
{
dict.Add(
task,
new NILoop.HandleInfo {
handle = task.TaskHandle,
buffer_size = task.SamplesPerChannel * task.Nodes.Count,
samples_per_chan = task.SamplesPerChannel,
type = (int)NILoop.TASK_TYPE.TASK_TYPE_ANALOG_INPUT,
result = 0,
mutex_buffers = IntPtr.Zero
}
);
}
foreach (var task in _tasks.OfType <NidaqSessionDigitalIn>().Where(t => t.Nodes.Count > 0))
{
dict.Add(
task,
new NILoop.HandleInfo {
handle = task.TaskHandle,
buffer_size = task.SamplesPerChannel * task.Nodes.Count,
samples_per_chan = task.SamplesPerChannel,
type = (int)NILoop.TASK_TYPE.TASK_TYPE_DIGITAL_INPUT,
result = 0,
mutex_buffers = IntPtr.Zero
}
);
}
var hPoll = NILoop.start_polling(dict.Values.ToArray(), dict.Count);
while (!_stopThread)
{
foreach (var task in dict)
{
if (task.Key is NidaqSessionAnalogIn)
{
ProcessInputData(task.Key.Nodes, task.Value, _inputAnalogDataBuffers[task.Key.Device], sizeof(double), hPoll);
}
else if (task.Key is NidaqSessionDigitalIn)
{
ProcessInputData(task.Key.Nodes, task.Value, _inputDigitalDataBuffers[task.Key.Device], sizeof(uint), hPoll);
}
}
}
NILoop.stop_polling(hPoll);
}
private void ProcessInputData(IReadOnlyList <INidaqMetric> listeningPorts, NILoop.HandleInfo taskInfo, IntPtr buffer, int sample_size_bytes, int hPoll)
{
var result = NILoop.read_buffer(hPoll, taskInfo.handle, buffer, sample_size_bytes * (taskInfo.samples_per_chan * listeningPorts.Count));
switch (result)
{
case 3:
case 1:
// task not found
SessionGraph.AsyncEmergencyStop(null);
_stopThread = true;
break;
case 2:
// queue empty, ignore
Thread.Sleep(1);
break;
case 0:
var channelData = buffer;
foreach (var port in listeningPorts)
{
((IMetricInput)port).DistributeData(channelData, taskInfo.samples_per_chan);
channelData = IntPtr.Add(channelData, sample_size_bytes * taskInfo.samples_per_chan);
}
break;
default:
// read error
System.Diagnostics.Debug.WriteLine(NidaQmxHelper.GetError(result));
SessionGraph.AsyncEmergencyStop(null);
_stopThread = true;
break;
}
}