Switched the serial port over to using the .net frameworks serial port.

Extracted the serial port into it's own class and created a simpler command processing mechanism.

MeadeAutostar497.UnitTests/TelescopeControllerUnitTests.cs

@@ -1,8 +1,8 @@
 using System.Collections.Generic;
+using System.IO.Ports;
 using ASCOM;
 using ASCOM.MeadeAutostar497.Controller;
 using ASCOM.Utilities;
-using ASCOM.Utilities.Interfaces;
 using Moq;
 using NUnit.Framework;
 
@@ -11,26 +11,25 @@ namespace MeadeAutostar497.UnitTests
     [TestFixture]
     public class TelescopeControllerUnitTests
     {
-        private Mock<ISerial> serialMock;
+        private Mock<ISerialProcessor> serialMock;
 
         private readonly List<string> _availableComPorts = new List<string> { "COM1", "COM2", "COM3" };
         private TelescopeController _telescopeController;
 
-        private string transmittedString;
+        private string _stringToRecieve = string.Empty;
-        private string stringToRecieve;
+        private bool _isConnected = false;
 
         [SetUp]
         public void Setup()
         {
-            transmittedString = string.Empty;
+            _stringToRecieve = string.Empty;
-            stringToRecieve = string.Empty;
+            _isConnected = false;
 
-            serialMock = new Mock<ISerial>();
+            serialMock = new Mock<ISerialProcessor>();
             serialMock.SetupAllProperties();
-
+            serialMock.Setup(x => x.GetPortNames()).Returns( () => _availableComPorts.ToArray());
-            serialMock.Setup(x => x.AvailableComPorts).Returns( () => _availableComPorts.ToArray());
+            serialMock.Setup(x => x.CommandTerminated(It.IsAny<string>(), It.IsAny<string>())).Returns(() => _stringToRecieve);
-            serialMock.Setup(X => X.Transmit(It.IsAny<string>())).Callback<string>(str => { transmittedString = str; });
+            serialMock.Setup(x => x.IsOpen).Returns(() => _isConnected);
-            serialMock.Setup(X => X.Receive()).Returns(() => stringToRecieve);
 
             _telescopeController = TelescopeController.Instance;
             _telescopeController.SerialPort = serialMock.Object;
@@ -39,7 +38,6 @@ namespace MeadeAutostar497.UnitTests
         [TearDown]
         public void TearDown()
         {
-            _telescopeController.Connected = false;
             _telescopeController.Port = "COM1";            
         }
 
@@ -59,7 +57,8 @@ namespace MeadeAutostar497.UnitTests
         [Test]
         public void ConnectedCanBeSetTrue()
         {
-            stringToRecieve = "test#";
+            _stringToRecieve = "test#";
+            _isConnected = true;
 
             _telescopeController.Connected = true;
             Assert.That(_telescopeController.Connected, Is.True);
@@ -68,27 +67,30 @@ namespace MeadeAutostar497.UnitTests
         [Test]
         public void EnsureThatTheSerialCommunicationsAreSetCorrectly()
         {
-            Assert.That(serialMock.Object.Connected, Is.False);
+            Assert.That(serialMock.Object.IsOpen, Is.False);
-
-            stringToRecieve = "test#";
 
+            _stringToRecieve = "test#";
             _telescopeController.Connected = true;
+            _isConnected = true;
             Assert.That(_telescopeController.Connected, Is.True);
 
-            Assert.That(serialMock.Object.DTREnable, Is.False);
+            serialMock.Verify(x => x.Open(), Times.Once);
-            Assert.That(serialMock.Object.RTSEnable, Is.False);
+
-            Assert.That(serialMock.Object.Speed, Is.EqualTo(SerialSpeed.ps9600));
+            Assert.That(serialMock.Object.DtrEnable, Is.False);
+            Assert.That(serialMock.Object.RtsEnable, Is.False);
+            Assert.That(serialMock.Object.BaudRate, Is.EqualTo(9600));
             Assert.That(serialMock.Object.DataBits, Is.EqualTo(8));
-            Assert.That(serialMock.Object.StopBits, Is.EqualTo(SerialStopBits.One));
+            Assert.That(serialMock.Object.StopBits, Is.EqualTo(StopBits.One));
-            Assert.That(serialMock.Object.Parity, Is.EqualTo(SerialParity.None));
+            Assert.That(serialMock.Object.Parity, Is.EqualTo(Parity.None));
             Assert.That(serialMock.Object.PortName, Is.EqualTo(_telescopeController.Port));
-            Assert.That(serialMock.Object.Connected, Is.True);
+            Assert.That(serialMock.Object.IsOpen, Is.True);
+            
         }
 
         [Test]
         public void WhenOpensComPortToNonAutostarThrowException()
         {
-            Assert.That(serialMock.Object.Connected, Is.False);
+            Assert.That(serialMock.Object.IsOpen, Is.False);
             var exception = Assert.Throws<InvalidOperationException>(() => { _telescopeController.Connected = true; });
 
             Assert.That(exception.Message, Is.EqualTo("Failed to communicate with telescope."));
@@ -99,11 +101,12 @@ namespace MeadeAutostar497.UnitTests
         [Test]
         public void CannotChangeSerialPortObjectWhenConnected()
         {
-            stringToRecieve = "test#";
+            _stringToRecieve = "test#";
+            _isConnected = true;
 
             _telescopeController.Connected = true;
 
-            Mock<ISerial> newSerialMock = new Mock<ISerial>();
+            Mock<ISerialProcessor> newSerialMock = new Mock<ISerialProcessor>();
 
             var exception = Assert.Throws<InvalidOperationException>( () => { _telescopeController.SerialPort = newSerialMock.Object; });
 
@@ -128,7 +131,8 @@ namespace MeadeAutostar497.UnitTests
         [Test]
         public void SettingPortToValidPortWhenConnectedFails()
         {
-            stringToRecieve = "test#";
+            _stringToRecieve = "test#";
+            _isConnected = true;
 
             _telescopeController.Connected = true;
             var exception = Assert.Throws<InvalidOperationException>( () => _telescopeController.Port = "COM2");

MeadeAutostar497/AscomClasses/Telescope.cs

@@ -169,9 +169,9 @@ namespace ASCOM.MeadeAutostar497
         {
             CheckConnected("CommandBlind");
             // Call CommandString and return as soon as it finishes
-            this.CommandString(command, raw);
+            //this.CommandString(command, raw);
             // or
-            //throw new ASCOM.MethodNotImplementedException("CommandBlind");
+            throw new ASCOM.MethodNotImplementedException("CommandBlind");
             // DO NOT have both these sections!  One or the other
         }
 
@@ -187,8 +187,11 @@ namespace ASCOM.MeadeAutostar497
 
         public string CommandString(string command, bool raw)
         {
+            // it's a good idea to put all the low level communication with the device here,
+            // then all communication calls this function
+            // you need something to ensure that only one command is in progress at a time
             CheckConnected("CommandString");
-            return _telescopeController.CommandString(command, raw);
+            throw new ASCOM.MethodNotImplementedException("CommandString");
         }
 
         public void Dispose()

MeadeAutostar497/Controller/ITelescopeController.cs

@@ -1,15 +1,14 @@
 using System;
-using ASCOM.Utilities.Interfaces;
+using System.IO.Ports;
 
 namespace ASCOM.MeadeAutostar497.Controller
 {
     public interface ITelescopeController
     {
-        ISerial SerialPort { get; set; }
+        ISerialProcessor SerialPort { get; set; }
         string Port { get; set; }
         bool Connected { get; set; }
 
-        string CommandString(string command, bool raw);
         bool Slewing { get; }
         DateTime utcDate { get; set; }
     }

MeadeAutostar497/Controller/SerialProcessor.cs

@@ -0,0 +1,138 @@
+using System;
+using System.IO.Ports;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading;
+
+namespace ASCOM.MeadeAutostar497.Controller
+{
+    [ComVisible(false)]
+    public interface ISerialProcessor
+    {
+        bool IsOpen { get; }
+        bool DtrEnable { get; set; }
+        bool RtsEnable { get; set; }
+        int BaudRate { get; set; }
+        int DataBits { get; set; }
+        StopBits StopBits { get; set; }
+        Parity Parity { get; set; }
+        string PortName { get; set; }
+        string[]  GetPortNames();
+        void Open();
+        void Close();
+
+        string CommandTerminated(string command, string terminator);
+        char CommandChar(string command);
+        string ReadTerminated(string terminator);
+    }
+
+    [ComVisible(false)]
+    public class SerialProcessor : ISerialProcessor
+    {
+        private SerialPort _serialPort = new SerialPort();
+        private Mutex serialMutex = new Mutex();
+
+        public bool IsOpen => _serialPort.IsOpen;
+
+        public bool DtrEnable
+        {
+            get => _serialPort.DtrEnable;
+            set => _serialPort.DtrEnable = value;
+        }
+
+        public bool RtsEnable
+        {
+            get => _serialPort.RtsEnable;
+            set => _serialPort.RtsEnable = value;
+        }
+
+        public int BaudRate
+        {
+            get => _serialPort.BaudRate;
+            set => _serialPort.BaudRate = value;
+        }
+
+        public int DataBits
+        {
+            get => _serialPort.DataBits;
+            set => _serialPort.DataBits = value;
+        }
+
+        public StopBits StopBits
+        {
+            get => _serialPort.StopBits;
+            set => _serialPort.StopBits = value;
+        }
+
+        public Parity Parity
+        {
+            get => _serialPort.Parity;
+            set => _serialPort.Parity = value;
+        }
+
+        public string PortName
+        {
+            get => _serialPort.PortName;
+            set => _serialPort.PortName = value;
+        }
+
+        public string[] GetPortNames()
+        {
+            return SerialPort.GetPortNames();
+        }
+
+        public void Open()
+        {
+            _serialPort.Open();
+        }
+
+        public void Close()
+        {
+            _serialPort.Close();
+        }
+
+        public string CommandTerminated(string command, string terminator)
+        {
+            serialMutex.WaitOne();
+            try
+            {
+                _serialPort.Write(command);
+                string result = _serialPort.ReadTo("#");
+                return result;
+            }
+            finally
+            {
+                serialMutex.ReleaseMutex();
+            }
+        }
+
+        public char CommandChar(string command)
+        {
+            serialMutex.WaitOne();
+            try
+            {
+                _serialPort.Write(command);
+                var result = _serialPort.ReadChar();
+                return Convert.ToChar(result);
+            }
+            finally
+            {
+                serialMutex.ReleaseMutex();
+            }
+        }
+
+        public string ReadTerminated(string terminator)
+        {
+            serialMutex.WaitOne();
+            try
+            {
+                string result = _serialPort.ReadTo("#");
+                return result;
+            }
+            finally
+            {
+                serialMutex.ReleaseMutex();
+            }
+        }
+    }
+}

MeadeAutostar497/Controller/TelescopeController.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Configuration;
 using System.Data;
+using System.IO.Ports;
 using System.Linq;
 using System.Threading;
 using ASCOM.Utilities;
@@ -14,12 +15,10 @@ namespace ASCOM.MeadeAutostar497.Controller
 
         public static TelescopeController Instance => lazy.Value;
 
-        private Mutex serialMutex = new Mutex();
+        private ISerialProcessor _serialPort;
-
+        public ISerialProcessor SerialPort
-        private ISerial _serialPort;
-        public ISerial SerialPort
         {
-            get => _serialPort ?? (_serialPort = new Serial());
+            get => _serialPort ?? (_serialPort = new SerialProcessor());
             set
             {
                 if (_serialPort == value)
@@ -27,7 +26,7 @@ namespace ASCOM.MeadeAutostar497.Controller
 
                 if (_serialPort != null)
                 {
-                    if (_serialPort.Connected)
+                    if (_serialPort.IsOpen)
                         throw new InvalidOperationException("Please disconnect before changing the serial engine.");
                 }
 
@@ -55,12 +54,12 @@ namespace ASCOM.MeadeAutostar497.Controller
 
         private bool ValidPort(string value)
         {
-            return SerialPort.AvailableComPorts.Contains(value);
+            return SerialPort.GetPortNames().Contains(value);
         }
 
         public bool Connected
         {
-            get => SerialPort.Connected;
+            get => SerialPort.IsOpen;
             set
             {
                 if (value == Connected)
@@ -71,60 +70,48 @@ namespace ASCOM.MeadeAutostar497.Controller
                     //Connecting
                     try
                     {
-                        SerialPort.DTREnable = false;
+                        SerialPort.DtrEnable = false;
-                        SerialPort.RTSEnable = false;
+                        SerialPort.RtsEnable = false;
-                        SerialPort.Speed = SerialSpeed.ps9600;
+                        SerialPort.BaudRate = 9600;
                         SerialPort.DataBits = 8;
-                        SerialPort.StopBits = SerialStopBits.One;
+                        SerialPort.StopBits = StopBits.One;
-                        SerialPort.Parity = SerialParity.None;
+                        SerialPort.Parity = Parity.None;
                         SerialPort.PortName = Port;
-                        SerialPort.Connected = true;
+                        SerialPort.Open();
 
                         TestConnectionActive();
                     }
                     catch (Exception)
                     {
-                        SerialPort.Connected = false;
+                        if (SerialPort.IsOpen)
+                            SerialPort.Close();
                         throw;
                     }
                 }
                 else
                 {
                     //Disconnecting
-                    SerialPort.Connected = false;
+                    SerialPort.Close();
                 }
             }
         }
 
         private void TestConnectionActive()
         {
-            var firmwareVersionNumber = CommandString("GVN");
+            var firmwareVersionNumber = SerialPort.CommandTerminated(":GVN#", "#");
             if (string.IsNullOrEmpty(firmwareVersionNumber))
             {
                 throw new InvalidOperationException("Failed to communicate with telescope."); 
             }
         }
 
-        public string CommandString(string command)
-        {
-            return CommandString($"#:{command}#", false);
-        }
-
-        public string CommandString(string command, bool raw)
-        {
-            // it's a good idea to put all the low level communication with the device here,
-            // then all communication calls this function
-            // you need something to ensure that only one command is in progress at a time
-            return SerialCommand(command, true);
-        }
-
         public bool Slewing
         {
             get
             {
                 if (!Connected) return false;
 
-                var result = CommandString("D");
+                var result = SerialPort.CommandTerminated("#:D#", "#");
                 return result != string.Empty;
             }
         }
@@ -133,8 +120,8 @@ namespace ASCOM.MeadeAutostar497.Controller
         {
             get
             {
-                string telescopeDate = CommandString("GC");
+                string telescopeDate = SerialPort.CommandTerminated("#:GC#", "#");
-                string telescopeTime = CommandString("GL");
+                string telescopeTime = SerialPort.CommandTerminated("#:GL#", "#");
 
                 int month = telescopeDate.Substring(0, 2).ToInteger();
                 int day = telescopeDate.Substring(3, 2).ToInteger();
@@ -156,40 +143,22 @@ namespace ASCOM.MeadeAutostar497.Controller
             set
             {
                 //var result = SerialCommand(":SLHH:MM:SS#", true);
-                var timeResult = SerialCommand($"#:SL{value:hh:mm:ss}#", true);
+                var timeResult = SerialPort.CommandChar($"#:SL{value:hh:mm:ss}#");
-                if (timeResult != "1")
+                if (timeResult != '1')
                 {
                     throw new InvalidOperationException("Failed to set local time");
                 }
 
-                var dateResult = SerialCommand($"#:SC{value:MM/dd/yy}#", true);
+                var dateResult = SerialPort.CommandChar($"#:SC{value:MM/dd/yy}#");
-                if (dateResult.Substring(0,1) != "1")
+                if (dateResult != '1')
                 {
                     throw new InvalidOperationException("Failed to set local time");
                 }
+
+                SerialPort.ReadTerminated("#");
+                SerialPort.ReadTerminated("#");
             }
 
         }
-
-        private string SerialCommand(string command, bool expectsResult )
-        {
-            serialMutex.WaitOne();
-            try
-            {
-                SerialPort.Transmit(command);
-                if (expectsResult)
-                {
-                    string result = SerialPort.ReceiveTerminated("#");
-
-                    return result;
-                }               
-                return string.Empty;
-            }
-            finally
-            {
-                SerialPort.ClearBuffers();
-                serialMutex.ReleaseMutex();
-            }
-        }
     }
 }

MeadeAutostar497/MeadeAutostar497.csproj

@@ -90,6 +90,7 @@
   <ItemGroup>
     <Compile Include="AscomClasses\Telescope.cs" />
     <Compile Include="Controller\ITelescopeController.cs" />
+    <Compile Include="Controller\SerialProcessor.cs" />
     <Compile Include="Controller\TelescopeController.cs" />
     <Compile Include="StringExtensions.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />