Threaded RS232

gistfile1.cs

#region usings
using System;
using System.ComponentModel.Composition;
using System.IO.Ports;
using System.Threading;

using VVVV.PluginInterfaces.V1;
using VVVV.PluginInterfaces.V2;
using VVVV.Utils.VColor;
using VVVV.Utils.VMath;

using VVVV.Core.Logging;
#endregion usings

namespace VVVV.Nodes
{
	class SerialInstance : IDisposable
	{
		bool FNeedsSend = true;
		string FMessageTx = "";
		
		bool FNewReceive = true;
		string FMessageRx = "";
		
		string FStatus = "";
		
		bool FRunning = false;
		Thread FThread = null;
		
		SerialPort FSerialPort = null;
		
		//settings
		string FPort = "";
		int FBaud = 0;
		
		public void Dispose()
		{
			Close();
		}
		
		public void Initialise(string port, int baud)
		{
			if (FPort == port && FBaud == baud)
				return;
			
			Close();
			
			FPort = port;
			FBaud = baud;
			
			Open();
		}
		
		public void Open()
		{
			try
			{
				FSerialPort = new SerialPort(FPort, FBaud, Parity.None, 8, StopBits.One);
				FSerialPort.DataReceived += new SerialDataReceivedEventHandler(DataReceived);
				FSerialPort.Open();
				FStatus = "Port opened";
			}
			catch
			{
				Close();
				FStatus = "Port open failed";
				return;
			}
			
			FRunning = true;
			FThread = new Thread(fnThread);
			FThread.Start();
		}
		
		public void Send(string message)
		{
			FMessageTx = message;
			FNeedsSend = true;
		}
		
		public string Receive()
		{
			if (FNewReceive)
			{
				FNewReceive = false;
				return FMessageRx;
			} else
				return "";
		}
		
		public bool IsOpen
		{
			get
			{
				return FSerialPort.IsOpen && FRunning;
			}
		}
		
		public string Status
		{
			get
			{
				return FStatus;
			}
		}
		
		private void DataReceived(object sender, SerialDataReceivedEventArgs e)
		{
			FStatus = "Data received";
			
			SerialPort sp = (SerialPort)sender;
			if (!FNewReceive)
				FMessageRx = sp.ReadExisting();
			else
				FMessageRx = FMessageRx + sp.ReadExisting();
		}
		
		private void fnThread()
		{
			while (FRunning)
			{
				if (FNeedsSend)
				{
					FSerialPort.Write(FMessageTx);
					FNeedsSend = false;
				}
				
				Thread.Sleep(1);
			}
		}
		
		void Close()
		{
			if (!FRunning)
				return;
			
			FRunning = false;
			FThread.Join(100);
			FSerialPort.Close();
			FSerialPort.Dispose();
		}
	}
	#region PluginInfo
	[PluginInfo(Name = "SerialPort", Category = "Devices", Version = "Threaded", Help = "Send and receive data over the serial port in a seperate thread per port", Tags = "")]
	#endregion PluginInfo
	public class ThreadedDevicesRS232Node : IPluginEvaluate, IDisposable
	{
		#region fields & pins
		[Input("Input", DefaultString = "hello c#")]
		ISpread<string> FInput;

		[Input("Port", DefaultString = "COM1")]
		ISpread<string> FPort;
		
		[Input("Baud", DefaultValue = 115200)]
		ISpread<int> FBaud;
		
		[Input("Send", IsBang = true)]
		ISpread<bool> FSend;
		
		[Output("Output")]
		ISpread<string> FOutput;
		
		[Output("Open")]
		ISpread<bool> FOpen;
		
		[Output("Status")]
		ISpread<string> FStatus;

		[Import()]
		ILogger FLogger;
		
		Spread<SerialInstance> FInstances = new Spread<SerialInstance>(0);
		#endregion fields & pins
		
		public void Dispose()
		{
			FLogger.Log(LogType.Debug, "Disposing SerialPort node");
			for (int i=0; i<FInstances.SliceCount; i++)
			{
				FInstances[i].Dispose();
			}
		}
		
		//called when data for any output pin is requested
		public void Evaluate(int SpreadMax)
		{
			FOutput.SliceCount = SpreadMax;
			FOpen.SliceCount = SpreadMax;
			FStatus.SliceCount = SpreadMax;
			
			Resize(SpreadMax);
			
			for (int i=0; i<SpreadMax; i++)
			{
				if (FSend[i])
				{
					if (!FInstances[i].IsOpen)
						FInstances[i].Open();
					
					FInstances[i].Send(FInput[i]);
				}
				FOutput[i] = FInstances[i].Receive();
				FOpen[i] = FInstances[i].IsOpen;
				FStatus[i] = FInstances[i].Status;
			}

			//FLogger.Log(LogType.Debug, "Logging to Renderer (TTY)");
		}
		
		private void Resize(int count)
		{
			FInstances.SliceCount = count;
			for (int i=0; i<count; i++)
			{
				if (FInstances[i] == null)
					FInstances[i] = new SerialInstance();
				
				FInstances[i].Initialise(FPort[i], FBaud[i]);
			}
		}
	}
}