Added method to wait till all queued commands are processed;

Added method to request data by pid

OBD.NET/OBD.NET.Common/Devices/ELM327.cs

@@ -1,5 +1,7 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
 using System.Threading.Tasks;
 using OBD.NET.Common.Commands;
 using OBD.NET.Common.Communication;
@@ -80,6 +82,7 @@ namespace OBD.NET.Common.Devices
                 Logger?.WriteLine("Setting the Protocol to 'Auto' ...", OBDLogLevel.Debug);
                 SendCommand(ATCommand.SetProtocolAuto);
 
+                WaitQueue();
             }
             // DarthAffe 21.02.2017: This seems to happen sometimes, i don't know why - just retry.
             catch
@@ -108,7 +111,11 @@ namespace OBD.NET.Common.Devices
             RequestData(pid);
         }
 
-        protected virtual void RequestData(byte pid)
+        /// <summary>
+        /// Request data based on a pid
+        /// </summary>
+        /// <param name="pid">The pid of the requested data</param>
+        public virtual void RequestData(byte pid)
         {
             Logger?.WriteLine("Requesting PID " + pid.ToString("X2") + " ...", OBDLogLevel.Debug);
             SendCommand(((byte)Mode).ToString("X2") + pid.ToString("X2"));
@@ -124,11 +131,20 @@ namespace OBD.NET.Common.Devices
         {
             Logger?.WriteLine("Requesting Type " + typeof(T).Name + " ...", OBDLogLevel.Debug);
             byte pid = ResolvePid<T>();
+            return await RequestDataAsync(pid) as T;
+        }
+
+        /// <summary>
+        /// Request data based on a pid
+        /// </summary>
+        /// <param name="pid">The pid of the requested data</param>
+        public virtual async Task<object> RequestDataAsync(byte pid)
+        {
             Logger?.WriteLine("Requesting PID " + pid.ToString("X2") + " ...", OBDLogLevel.Debug);
             CommandResult result = SendCommand(((byte)Mode).ToString("X2") + pid.ToString("X2"));
 
             await result.WaitHandle.WaitAsync();
-            return result.Result as T;
+            return result.Result;
         }
 
         protected override object ProcessMessage(string message)
@@ -168,16 +184,42 @@ namespace OBD.NET.Common.Devices
             where T : class, IOBDData, new()
         {
             if (!PidCache.TryGetValue(typeof(T), out byte pid))
-            {
+                pid = AddToPidCache<T>();
-                T data = Activator.CreateInstance<T>();
-                pid = data.PID;
-                PidCache.Add(typeof(T), pid);
-                DataTypeCache.Add(pid, typeof(T));
-            }
 
             return pid;
         }
 
+        public virtual byte AddToPidCache<T>()
+            where T : class, IOBDData, new() => AddToPidCache(typeof(T));
+
+        protected virtual byte AddToPidCache(Type obdDataType)
+        {
+            IOBDData data = (IOBDData)Activator.CreateInstance(obdDataType);
+            if (data == null) throw new ArgumentException("Has to implement IOBDData", nameof(obdDataType));
+
+            byte pid = data.PID;
+
+            PidCache.Add(obdDataType, pid);
+            DataTypeCache.Add(pid, obdDataType);
+
+            return pid;
+        }
+
+        /// <summary>
+        /// YOU SHOULDN'T NEED THIS METHOD!
+        /// 
+        /// You should only use this method if you're requesting data by pid instead of the <see cref="RequestData{T}"/>-method.
+        /// 
+        /// Initializes the PID-Cache with all IOBDData-Types contained in OBD.NET.
+        /// You can add additional ones with <see cref="AddToPidCache{T}"/>.
+        /// </summary>
+        public virtual void InitializePidCache()
+        {
+            TypeInfo iobdDataInfo = typeof(IOBDData).GetTypeInfo();
+            foreach (TypeInfo obdDataType in iobdDataInfo.Assembly.DefinedTypes.Where(t => t.IsClass && !t.IsAbstract && iobdDataInfo.IsAssignableFrom(t)))
+                AddToPidCache(obdDataType.AsType());
+        }
+
         public override void Dispose() => Dispose(true);
 
         public void Dispose(bool sendCloseProtocol)

OBD.NET/OBD.NET.Common/Devices/SerialDevice.cs

@@ -23,6 +23,11 @@ namespace OBD.NET.Common.Devices
         private Task _commandWorkerTask;
         private CancellationTokenSource _commandCancellationToken;
 
+        private volatile int _queueSize = 0;
+        private readonly ManualResetEvent _queueEmptyEvent = new ManualResetEvent(true);
+
+        public int QueueSize => _queueSize;
+
         protected QueuedCommand CurrentCommand;
         protected IOBDLogger Logger { get; }
         protected ISerialConnection Connection { get; }
@@ -102,6 +107,8 @@ namespace OBD.NET.Common.Devices
             Logger?.WriteLine("Queuing Command: '" + command.Replace('\r', '\'') + "'", OBDLogLevel.Verbose);
 
             QueuedCommand cmd = new QueuedCommand(command);
+            _queueEmptyEvent.Reset();
+            _queueSize++;
             _commandQueue.Add(cmd);
 
             return cmd.CommandResult;
@@ -193,8 +200,14 @@ namespace OBD.NET.Common.Devices
             while (!_commandCancellationToken.IsCancellationRequested)
             {
                 CurrentCommand = null;
-                if (_commandQueue.TryTake(out CurrentCommand, Timeout.Infinite, _commandCancellationToken.Token))
+
+                if (_queueSize == 0)
+                    _queueEmptyEvent.Set();
+
+                if (_commandQueue.TryTake(out CurrentCommand, 10, _commandCancellationToken.Token))
                 {
+                    _queueSize--;
+
                     Logger?.WriteLine("Writing Command: '" + CurrentCommand.CommandText.Replace('\r', '\'') + "'", OBDLogLevel.Verbose);
 
                     if (Connection.IsAsync)
@@ -208,6 +221,10 @@ namespace OBD.NET.Common.Devices
             }
         }
 
+        public void WaitQueue() => _queueEmptyEvent.WaitOne();
+
+        public async Task WaitQueueAsync() => await Task.Run(() => WaitQueue());
+
         /// <summary>
         /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
         /// </summary>

OBD.NET/OBD.NET.Common/Logging/OBDDebugLogger.cs

@@ -1,4 +1,5 @@
-using System.Diagnostics;
+using System;
+using System.Diagnostics;
 
 namespace OBD.NET.Common.Logging
 {
@@ -8,9 +9,31 @@ namespace OBD.NET.Common.Logging
     /// <seealso cref="IOBDLogger" />
     public class OBDDebugLogger : IOBDLogger
     {
+
+        #region Properties & Fields
+
+        public OBDLogLevel LogLevel { get; set; }
+
+        #endregion
+
+        #region Constructors
+
+        public OBDDebugLogger(OBDLogLevel level = OBDLogLevel.None)
+        {
+            this.LogLevel = level;
+        }
+
+        #endregion
+
         #region Methods
 
-        public void WriteLine(string text, OBDLogLevel level) => Debug.WriteLine($"{level}: {text}");
+        public void WriteLine(string text, OBDLogLevel level)
+        {
+            if (LogLevel == OBDLogLevel.None) return;
+
+            if ((int)level <= (int)LogLevel)
+                Debug.WriteLine($"{DateTime.Now:G} -  {level} -  {text}");
+        }
 
         #endregion
     }

OBD.NET/ODB.NET.ConsoleClient/Program.cs

@@ -2,6 +2,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using OBD.NET.Common.Devices;
+using OBD.NET.Common.Extensions;
 using OBD.NET.Common.Logging;
 using OBD.NET.Common.OBDData;
 using ODB.NET.Desktop.Communication;
@@ -25,9 +26,10 @@ namespace ODB.NET.ConsoleClient
             using (ELM327 dev = new ELM327(connection, new OBDConsoleLogger(OBDLogLevel.Debug)))
             {
                 dev.SubscribeDataReceived<EngineRPM>((sender, data) => Console.WriteLine("EngineRPM: " + data.Data.Rpm));
-
                 dev.SubscribeDataReceived<VehicleSpeed>((sender, data) => Console.WriteLine("VehicleSpeed: " + data.Data.Speed));
 
+                dev.SubscribeDataReceived<IOBDData>((sender, data) => Console.WriteLine($"PID {data.Data.PID.ToHexString()}: {data.Data}"));
+
                 dev.Initialize();
                 dev.RequestData<FuelType>();
                 for (int i = 0; i < 5; i++)
@@ -40,9 +42,9 @@ namespace ODB.NET.ConsoleClient
             Console.ReadLine();
 
             //Async example
-            MainAsync(comPort).Wait();
+            //MainAsync(comPort).Wait();
 
-            Console.ReadLine();
+            //Console.ReadLine();
         }
 
         /// <summary>

OBD.NET/ODB.NET.Desktop/Logging/ODBConsoleLogger.cs

@@ -30,7 +30,7 @@ namespace ODB.NET.Desktop.Logging
         {
             if (LogLevel == OBDLogLevel.None) return;
 
-            if ((int)level >= (int)LogLevel)
+            if ((int)level <= (int)LogLevel)
                 Console.WriteLine($"{DateTime.Now:G} -  {level} -  {text}");
         }