Merge pull request #41 from WildernessLabs/feature/modbusdevice

ModnusPolledDevice support
WildernessLabs · Feb 6, 2024 · bde6b5a · bde6b5a
2 parents dc52cbd + 98da92b
commit bde6b5a
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Showing 4 changed files with 660 additions and 9 deletions.
diff --git a/src/Meadow.Modbus.Unit.Tests/ModbusSerialTStatTests.cs b/src/Meadow.Modbus.Unit.Tests/ModbusSerialTStatTests.cs
@@ -5,8 +5,108 @@
 
 namespace Meadow.Modbus.Unit.Tests;
 
+public class TStat8 : ModbusPolledDevice
+{
+    private float _currentSetPoint;
+
+    private const ushort SetPointRegister = 345;
+
+    public TStat8(ModbusRtuClient client, byte modbusAddress, TimeSpan? refreshPeriod = null)
+        : base(client, modbusAddress, refreshPeriod)
+    {
+        MapHoldingRegistersToProperty(
+            startRegister: 121,
+            registerCount: 1,
+            propertyName: nameof(Temperature),
+            scale: 0.10); // value is in 0.1 deg
+
+        // map to a field, not a property as the property setter needs to perform an action
+        MapHoldingRegistersToField(
+            startRegister: SetPointRegister,
+            registerCount: 1,
+            fieldName: nameof(_currentSetPoint),
+            scale: 0.10);
+
+        MapHoldingRegistersToProperty(
+            startRegister: 198,
+            registerCount: 1,
+            propertyName: nameof(Humidity));
+
+        MapHoldingRegistersToProperty(
+            startRegister: 364, // not scaled by 0.1
+            registerCount: 1,
+            propertyName: nameof(PowerUpSetPoint));
+
+        MapHoldingRegistersToProperty(
+            startRegister: 365,
+            registerCount: 1,
+            propertyName: nameof(MaxSetPoint));
+
+        MapHoldingRegistersToProperty(
+            startRegister: 366,
+            registerCount: 1,
+            propertyName: nameof(MinSetPoint));
+
+        MapHoldingRegistersToProperty(
+            startRegister: 410,
+            registerCount: 7,
+            propertyName: nameof(Clock),
+            conversionFunction: ConvertRegistersToClockTime);
+    }
+
+    private object ConvertRegistersToClockTime(ushort[] data)
+    {
+        // data[2] is week, so ignore
+        return new DateTime(data[0], data[1], data[3], data[4], data[5], data[6]);
+    }
+
+    public DateTime Clock { get; private set; }
+    public int Humidity { get; private set; }
+    public float Temperature { get; private set; }
+    public float MinSetPoint { get; private set; }
+    public float MaxSetPoint { get; private set; }
+    public float PowerUpSetPoint { get; private set; }
+
+    public float SetPoint
+    {
+        get => _currentSetPoint;
+        set
+        {
+            _ = WriteHoldingRegister(SetPointRegister, (ushort)(value * 10));
+        }
+    }
+}
+
 public class ModbusSerialTStatTests
 {
+    // this class assumes a connected serial Temco Controls TSTAT7 or TSTAT8
+    [Fact]
+    public async void PolledDevicetest()
+    {
+        using (var port = new SerialPortShim("COM3", 19200, Hardware.Parity.None, 8, Hardware.StopBits.One))
+        {
+            port.ReadTimeout = TimeSpan.FromSeconds(15);
+            port.Open();
+
+            var client = new ModbusRtuClient(port);
+            var tstat = new TStat8(client, 201, TimeSpan.FromSeconds(1));
+            tstat.StartPolling();
+
+            var i = 0;
+            while (true)
+            {
+                await Task.Delay(1000);
+                Debug.WriteLine($"Temp: {tstat.Temperature}");
+                Debug.WriteLine($"SetPoint: {tstat.SetPoint}");
+                Debug.WriteLine($"MinSetPoint: {tstat.MinSetPoint}");
+                Debug.WriteLine($"MaxSetPoint: {tstat.MaxSetPoint}");
+                Debug.WriteLine($"PowerUpSetPoint: {tstat.PowerUpSetPoint}");
+                Debug.WriteLine($"Humidity: {tstat.Humidity}");
+                Debug.WriteLine($"Clock: {tstat.Clock}");
+            }
+        }
+    }
+
     // this class assumes a connected serial Temco Controls TSTAT7 or TSTAT8
     [Fact(Skip = "Requires a connected TSTAT8 over RS485")]
     public async void MultipleReadHoldingRegisterTest()
@@ -33,10 +133,10 @@ public async void MultipleReadHoldingRegisterTest()
         }
     }
 
-    [Fact(Skip = "Requires a connected TSTAT8 over RS485")]
+    [Fact]
     public async void MultipleWriteHoldingRegisterTest()
     {
-        using (var port = new SerialPortShim("COM4", 19200, Hardware.Parity.None, 8, Hardware.StopBits.One))
+        using (var port = new SerialPortShim("COM3", 19200, Hardware.Parity.None, 8, Hardware.StopBits.One))
         {
             port.ReadTimeout = TimeSpan.FromSeconds(15);
             port.Open();

diff --git a/src/Meadow.Modbus/Clients/ModbusClientBase.cs b/src/Meadow.Modbus/Clients/ModbusClientBase.cs
@@ -17,6 +17,7 @@ public abstract class ModbusClientBase : IModbusBusClient, IDisposable
     private const int MaxCoilReadCount = 0x7d0;
     private const int MaxRegisterWriteCount = 0x7b;
     private const int MaxCoilWriteCount = 0x7b0;
+    private const int LockTimeoutMs = 2000;
 
     /// <summary>
     /// Event triggered when the client is disconnected.
@@ -143,7 +144,10 @@ public async Task WriteHoldingRegister(byte modbusAddress, ushort register, usho
         // swap endianness, because Modbus
         var data = BitConverter.GetBytes(IPAddress.HostToNetworkOrder((short)value));
         var message = GenerateWriteMessage(modbusAddress, ModbusFunction.WriteRegister, register, data);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return;
+        }
 
         try
         {
@@ -185,7 +189,10 @@ public async Task WriteHoldingRegisters(byte modbusAddress, ushort startRegister
         var data = values.SelectMany(i => BitConverter.GetBytes(IPAddress.HostToNetworkOrder((short)i))).ToArray();
 
         var message = GenerateWriteMessage(modbusAddress, ModbusFunction.WriteMultipleRegisters, startRegister, data);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return;
+        }
 
         try
         {
@@ -237,7 +244,10 @@ public async Task<ushort[]> ReadHoldingRegisters(byte modbusAddress, ushort star
         }
 
         var message = GenerateReadMessage(modbusAddress, ModbusFunction.ReadHoldingRegister, startRegister, registerCount);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return Array.Empty<ushort>();
+        }
 
         byte[] result;
 
@@ -279,7 +289,10 @@ public async Task<ushort[]> ReadInputRegisters(byte modbusAddress, ushort startR
         if (registerCount > MaxRegisterReadCount) throw new ArgumentException($"A maximum of {MaxRegisterReadCount} registers can be retrieved at one time");
 
         var message = GenerateReadMessage(modbusAddress, ModbusFunction.ReadInputRegister, startRegister, registerCount);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return Array.Empty<ushort>();
+        }
 
         byte[] result;
 
@@ -308,7 +321,11 @@ public async Task WriteCoil(byte modbusAddress, ushort register, bool value)
 
         var message = GenerateWriteMessage(modbusAddress, ModbusFunction.WriteCoil, register, data);
 
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return;
+        }
+
         try
         {
             await DeliverMessage(message);
@@ -339,7 +356,10 @@ public async Task WriteMultipleCoils(byte modbusAddress, ushort startRegister, I
         new BitArray(values.ToArray()).CopyTo(msgSegment, 3); // Concatinate bool binary values list as converted bytes
 
         var message = GenerateWriteMessage(modbusAddress, ModbusFunction.WriteMultipleCoils, startRegister, msgSegment);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return;
+        }
 
         try
         {
@@ -362,7 +382,10 @@ public async Task<bool[]> ReadCoils(byte modbusAddress, ushort startCoil, int co
         if (coilCount > MaxCoilReadCount) throw new ArgumentException($"A maximum of {MaxCoilReadCount} coils can be retrieved at one time");
 
         var message = GenerateReadMessage(modbusAddress, ModbusFunction.ReadCoil, startCoil, coilCount);
-        await _syncRoot.WaitAsync();
+        if (!await _syncRoot.WaitAsync(LockTimeoutMs))
+        {
+            return Array.Empty<bool>();
+        }
 
         byte[] result;
 

diff --git a/src/Meadow.Modbus/Clients/ModbusRtuClient.cs b/src/Meadow.Modbus/Clients/ModbusRtuClient.cs
@@ -36,6 +36,7 @@ public class ModbusRtuClient : ModbusClientBase
     public ModbusRtuClient(ISerialPort port, IDigitalOutputPort? enablePort = null)
     {
         _port = port;
+        _port.WriteTimeout = _port.ReadTimeout = TimeSpan.FromSeconds(5);
         _enable = enablePort;
     }