Example: Protocol configuration in event mode

An example of a NetLogic contained in the serial
object that uses the event mode to read data sent asynchronously from a device. The
method, linked to the button pressing event, enables you to stop the current reading and start a new reading.
To use the event mode, you must set the
property to
. This way,
will be blocking as long as the requested data do not arrive on the serial port.
You can stop the reading with the
method, or the
method. In both cases, a
exception is generated. To carry out a clean close of the NetLogic, you must terminate any pending read operations by calling the
method in the NetLogic
You can download a sample project from SerialPortDemoEventMode.zip.
public class RuntimeNetlogic1 : BaseNetLogic { private SerialPort serialPort; private LongRunningTask task; public override void Start() { serialPort = (SerialPort)Owner; serialPort.Timeout = TimeSpan.FromMilliseconds(0.0); task = new LongRunningTask(Run, Owner); task.Start(); } [ExportMethod] public void OnClick() { // Cancel current read serialPort.CancelRead(); task.Cancel(); // Start new read task = new LongRunningTask(Run, Owner); task.Start(); } private void Run() { while(!task.IsCancellationRequested) { try { // Block until 3 bytes arrive on serial var result = serialPort.ReadBytes(3); foreach (var b in result) Log.Info(String.Format("0x{0:x2}", b)); } catch (ReadCanceledException ex) { // In case of read canceled, exit from the loop Log.Info(ex.Message); return; } catch (Exception e) { Log.Error(e.Message); } } } public override void Stop() { // Explicit call to Close to cancel pending read (if any) serialPort.Close(); task.Cancel(); } }
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