CAN Immitate

BusCommPractice/BusCommPracticeConsoleApp/CANs/CANBus.cs

@@ -0,0 +1,37 @@
+using BusCommPracticeConsoleApp.Models;
+
+namespace BusCommPracticeConsoleApp.CANs
+{
+    public class CANBus
+    {
+        private readonly List<CANNode> _nodes = new List<CANNode>();
+        private CanFrame _currentFrame = null;
+
+        public void AddNode(CANNode node)
+        {
+            _nodes.Add(node);
+            node.ConnectToBus(this);
+        }
+
+        public void SendFrame(CANNode sender, CanFrame frame)
+        {
+            if (_currentFrame != null && frame.ID >= _currentFrame.ID)
+            {
+                Console.WriteLine("Already higher priority frame is used.");
+                return;
+            }
+
+            _currentFrame = frame;
+            Console.WriteLine($"{sender.Name} node send the frame{Environment.NewLine}{frame}");
+        }
+
+        public void CompleteTransmission()
+        {
+            if (_currentFrame == null)
+                return;
+
+            Console.WriteLine($"Send 0x{_currentFrame.ID.ToString("X8")} frame complete.");
+            _currentFrame = null;
+        }
+    }
+}

BusCommPractice/BusCommPracticeConsoleApp/CANs/CANNode.cs

@@ -0,0 +1,35 @@
+namespace BusCommPracticeConsoleApp.CANs
+{
+    public class CANNode
+    {
+        public string Name { get; set; }
+        private CANBus _bus;
+
+        public CANNode(string name)
+        {
+            Name = name;
+        }
+
+        public void ConnectToBus(CANBus bus)
+        {
+            _bus = bus;
+        }
+
+        public void SendMessage(uint id, byte[] data)
+        {
+            var frame = new CanFrame(id, false, data);
+            _bus.SendFrame(this, frame);
+        }
+
+        public void ReceiveFrame(CanFrame frame)
+        {
+            if (frame.CRC != frame.CRC)
+                Console.WriteLine("<{Name}> node CRC check error!");
+        }
+
+        public void AcknowledgeFrame()
+        {
+            Console.WriteLine($"<{Name}> node acknowledged.");
+        }
+    }
+}

BusCommPractice/BusCommPracticeConsoleApp/CANs/CanFrame.cs

@@ -0,0 +1,65 @@
+using System.Text;
+
+namespace BusCommPracticeConsoleApp.CANs
+{
+    public class CanFrame
+    {
+        // Field Define
+        public bool SOF { get; set; } = true;       // Start of Frame (1bit)
+        public uint ID { get; set; }                // Identifier (29bits)
+        public bool RTR { get; set; }               // Remote Transmittion Request (1bit)
+        public byte DLC { get; set; }               // Data Length Code (4bit, 0~8)
+        public byte[] Data { get; set; }            // Data Field (0~8 bytes)
+        public ushort CRC { get; set; }             // Cyclic Redundancy Check (15bits)
+        public bool ACK { get; set; }               // Acknowledge (1bit)
+        public byte EOF { get; set; }               // End of Frame (7bits, all 1)
+
+        public CanFrame(uint id, bool rtr, byte[] data)
+        {
+            if (id > 0x1FFFFFFF) // 29bits check
+                throw new ArgumentException("The id cannot larger than 29bits.");
+            
+            if (data.Length > 8)
+                throw new ArgumentException("The data length cannot larger than 8bytes.");
+            
+            ID = id;
+            RTR = rtr;
+            DLC = (byte)data.Length;
+            Data = data;
+            CRC = CalculateCRC();
+            ACK = false;
+        }
+
+        private ushort CalculateCRC()
+        {
+            uint crc = ID;
+            crc += RTR ? 1u : 0u;
+            crc += DLC;
+            foreach (var c in Data)
+                crc += c;
+            
+            return (ushort)(crc & 0x7FFF); // 15bits masking
+        }
+
+        public override string ToString()
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine("=== CAN 2.0B Frame ===");
+            sb.AppendLine($"SOF: {SOF}");
+            sb.AppendLine($"ID: 0x{ID:X8}");
+            sb.AppendLine($"RTR: {RTR}");
+            sb.AppendLine($"DLC: {DLC}");
+            sb.Append("Data: ");
+            for (int i = 0; i < DLC; i++)
+            {
+                sb.Append($"0x{Data[i]:X2} ");
+            }
+            sb.AppendLine();
+            sb.AppendLine($"CRC: 0x{CRC:X4}");
+            sb.AppendLine($"ACK: {ACK}");
+            sb.AppendLine($"EOF: 0b{Convert.ToString(EOF, 2).PadLeft(7, '0')}");
+            sb.AppendLine("======================");
+            return sb.ToString();
+        }
+    }
+}

BusCommPractice/BusCommPracticeConsoleApp/Program.cs

@@ -1,4 +1,6 @@
-using BusCommPracticeConsoleApp.Models;
+using System.Text;
+using BusCommPracticeConsoleApp.CANs;
+using BusCommPracticeConsoleApp.Models;
 
 namespace BusCommPracticeConsoleApp;
 
@@ -6,21 +8,48 @@ class Program
 {
     static void Main(string[] args)
     {
-        IMessageBus messageBus1= new MessageBus();
+        /**********************
-        IMessageBus messageBus2= new MessageBus();
+            MESSAGE BUS
+        **********************/
 
-        var subscriber1 = new Subscriber(messageBus1, "Sub1");
+        // IMessageBus messageBus1= new MessageBus();
-        var subscriber2 = new Subscriber(messageBus1, "Sub2");
+        // IMessageBus messageBus2= new MessageBus();
-        var subscriber3 = new Subscriber(messageBus2, "Sub3");
 
-        var publisher1 = new Publisher(messageBus1);
+        // var subscriber1 = new Subscriber(messageBus1, "Sub1");
-        var publisher2 = new Publisher(messageBus2);
+        // var subscriber2 = new Subscriber(messageBus1, "Sub2");
+        // var subscriber3 = new Subscriber(messageBus2, "Sub3");
 
-        publisher1.SendMessage("Hello, Bus!");
+        // var publisher1 = new Publisher(messageBus1);
-        publisher1.SendMessage("I'm publisher 1");
+        // var publisher2 = new Publisher(messageBus2);
 
-        publisher2.SendMessage("Hello, Bus!");
+        // publisher1.SendMessage("Hello, Bus!");
-        publisher2.SendMessage("I'm publisher 2");
+        // publisher1.SendMessage("I'm publisher 1");
+
+        // publisher2.SendMessage("Hello, Bus!");
+        // publisher2.SendMessage("I'm publisher 2");
+
+        
+        /**********************
+            CAN BUS
+        **********************/
+        var bus = new CANBus();
+        
+        var nodeA = new CANNode("NodeA");
+        var nodeB = new CANNode("NodeB");
+        var nodeC = new CANNode("NodeC");
+
+        bus.AddNode(nodeA);
+        bus.AddNode(nodeB);
+        bus.AddNode(nodeC);
+
+        nodeA.SendMessage(0x1ABCDEFF, Encoding.UTF8.GetBytes("PHK"));
+        nodeB.SendMessage(0x0123F321, new byte[] { 0x55, 0x66, 0x77, 0x88 });
+
+        bus.CompleteTransmission();
+
+        Thread.Sleep(1000);
+        nodeC.SendMessage(0x12345678, new byte[] { 0x99, 0xAA, 0xBB, 0xCC });
+        bus.CompleteTransmission();
 
         Console.ReadLine();
     }