如何自動檢測Arduino COM端口？

Question

我使用一個Arduino與Firmata庫通訊C＃應用程序，和我想要消除的COM端口配置組件，因爲它可以從機改爲機...

是否有可能：

1. 枚舉系統中的COM端口列表？ （在我的谷歌搜索中，我已經看到一些相當醜陋的Win32 API代碼，希望現在可能有更清潔的版本）
2. 自動檢測哪個COM端口連接到Arduino？

Answer 1

這個代碼一點已經表現非常出色，這（返回COM口弦，即「COM12」如果檢測到的Arduino）：

private string AutodetectArduinoPort() 
     { 
      ManagementScope connectionScope = new ManagementScope(); 
      SelectQuery serialQuery = new SelectQuery("SELECT * FROM Win32_SerialPort"); 
      ManagementObjectSearcher searcher = new ManagementObjectSearcher(connectionScope, serialQuery); 

      try 
      { 
       foreach (ManagementObject item in searcher.Get()) 
       { 
        string desc = item["Description"].ToString(); 
        string deviceId = item["DeviceID"].ToString(); 

        if (desc.Contains("Arduino")) 
        { 
         return deviceId; 
        } 
       } 
      } 
      catch (ManagementException e) 
      { 
       /* Do Nothing */ 
      } 

      return null; 
     } 

Answer 2

1. 您可以使用SerialPort.GetPortNames()返回字符串COM端口名稱的數組。
2. 我不認爲你可以自動檢測端口，你必須ping設備，以查看設備是否連接。

Answer 3

試試這個，我工作的一個非常類似的項目，任何人都可以隨時編輯這個！

在Arduino代碼的設置部分，我調用了setupComms（）方法，這個方法只是打印一個「A」直到它接收到一個「a」。一旦收到「a」，它將跳轉到主循環（）函數。因此，C＃部分檢查每個可用端口的「A」，如果發現「A」，我們知道我們已經打開了Arduino的端口！

再次，這可能不是很乾淨，但它確實工作，我歡迎任何意見和建議！

foreach (string s in SerialPort.GetPortNames()) 
     { 
      com.Close(); // To handle the exception, in case the port isn't found and then they try again... 

      bool portfound = false; 
       com.PortName = s; 
       com.BaudRate = 38400; 
       try 
       { 
        com.Open(); 
        status.Clear(); 
        status.Text += "Trying port: " + s+"\r"; 
       } 
       catch (IOException c) 
       { 
        status.Clear(); 
        status.Text += "Invalid Port"+"\r"; 
        return; 
       } 
       catch (InvalidOperationException c1) 
       { 

        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       catch (ArgumentNullException c2) 
       { 
        // System.Windows.Forms.MessageBox.Show("Sorry, Exception Occured - " + c2); 
        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       catch (TimeoutException c3) 
       { 
        // System.Windows.Forms.MessageBox.Show("Sorry, Exception Occured - " + c3); 
        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       catch (UnauthorizedAccessException c4) 
       { 
        //System.Windows.Forms.MessageBox.Show("Sorry, Exception Occured - " + c); 
        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       catch (ArgumentOutOfRangeException c5) 
       { 
        //System.Windows.Forms.MessageBox.Show("Sorry, Exception Occured - " + c5); 
        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       catch (ArgumentException c2) 
       { 
        //System.Windows.Forms.MessageBox.Show("Sorry, Exception Occured - " + c2); 
        status.Clear(); 
        status.Text += "Invalid Port" + "\r"; 
        return; 
       } 
       if (!portfound) 
       { 
        if (com.IsOpen) // Port has been opened properly... 
        { 
         com.ReadTimeout = 500; // 500 millisecond timeout... 
         sent.Text += "Attemption to open port " + com.PortName + "\r"; 
         try 
         { 
          sent.Text += "Waiting for a response from controller: " + com.PortName + "\r"; 
          string comms = com.ReadLine(); 
          sent.Text += "Reading From Port " + com.PortName+"\r"; 
          if (comms.Substring(0,1) == "A") // We have found the arduino! 
          { 
           status.Clear(); 
           status.Text += s + com.PortName+" Opened Successfully!" + "\r"; 
           //com.Write("a"); // Sends 0x74 to the arduino letting it know that we are connected! 
           com.ReadTimeout = 200; 
           com.Write("a"); 
           sent.Text += "Port " + com.PortName + " Opened Successfully!"+"\r"; 
           brbox.Text += com.BaudRate; 
           comboBox1.Text = com.PortName; 

          } 
          else 
          { 
           sent.Text += "Port Not Found! Please cycle controller power and try again" + "\r"; 
           com.Close();  
          } 
         } 
         catch (Exception e1) 
         { 
          status.Clear(); 
          status.Text += "Incorrect Port! Trying again..."; 
          com.Close(); 
         } 
        } 
       } 
     } 

所有的Try Catch語句都在我最初測試的時候出現，這對我來說迄今爲止都有效。祝你好運！

Answer 4

把WMI管理路線做得更遠一點，我想出了一個包裝類，它掛接到Win32_SerialPorts事件並動態填充Arduino和Digi International（X-Bee）設備的SerialPorts列表， PortNames和BaudRates。

現在，我已經使用Win32_SerialPorts條目中的設備描述字段作爲字典的關鍵字，但這可以很容易地更改。

它已經通過Arduino UNO進行了有限容量的測試，看起來很穩定。

// ------------------------------------------------------------------------- 
// <copyright file="ArduinoDeviceManager.cs" company="ApacheTech Consultancy"> 
//  Copyright (c) ApacheTech Consultancy. All rights reserved. 
// </copyright> 
// <license type="GNU General Public License" version="3"> 
//  This program is free software: you can redistribute it and/or modify 
//  it under the terms of the GNU General Public License as published by 
//  the Free Software Foundation, either version 3 of the License, or 
//  (at your option) any later version. 
// 
//  This program is distributed in the hope that it will be useful, 
//  but WITHOUT ANY WARRANTY; without even the implied warranty of 
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
//  GNU General Public License for more details. 
// 
//  You should have received a copy of the GNU General Public License 
//  along with this program. If not, see http://www.gnu.org/licenses 
// <license> 
// ------------------------------------------------------------------------- 

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Diagnostics; 
using System.IO.Ports; 
using System.Linq; 
using System.Management; 
using System.Runtime.CompilerServices; 

// Automatically imported by Jetbeans Resharper 
using ArduinoLibrary.Annotations; 

namespace ArduinoLibrary 
{ 
    /// <summary> 
    ///  Provides automated detection and initiation of Arduino devices. This class cannot be inherited. 
    /// </summary> 
    public sealed class ArduinoDeviceManager : IDisposable, INotifyPropertyChanged 
    { 
     /// <summary> 
     ///  A System Watcher to hook events from the WMI tree. 
     /// </summary> 
     private readonly ManagementEventWatcher _deviceWatcher = new ManagementEventWatcher(new WqlEventQuery(
      "SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 2 OR EventType = 3")); 

     /// <summary> 
     ///  A list of all dynamically found SerialPorts. 
     /// </summary> 
     private Dictionary<string, SerialPort> _serialPorts = new Dictionary<string, SerialPort>(); 

     /// <summary> 
     ///  Initialises a new instance of the <see cref="ArduinoDeviceManager"/> class. 
     /// </summary> 
     public ArduinoDeviceManager() 
     { 
      // Attach an event listener to the device watcher. 
      _deviceWatcher.EventArrived += _deviceWatcher_EventArrived; 

      // Start monitoring the WMI tree for changes in SerialPort devices. 
      _deviceWatcher.Start(); 

      // Initially populate the devices list. 
      DiscoverArduinoDevices(); 
     } 

     /// <summary> 
     ///  Gets a list of all dynamically found SerialPorts. 
     /// </summary> 
     /// <value>A list of all dynamically found SerialPorts.</value> 
     public Dictionary<string, SerialPort> SerialPorts 
     { 
      get { return _serialPorts; } 
      private set 
      { 
       _serialPorts = value; 
       OnPropertyChanged(); 
      } 
     } 

     /// <summary> 
     ///  Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources. 
     /// </summary> 
     public void Dispose() 
     { 
      // Stop the WMI monitors when this instance is disposed. 
      _deviceWatcher.Stop(); 
     } 

     /// <summary> 
     ///  Occurs when a property value changes. 
     /// </summary> 
     public event PropertyChangedEventHandler PropertyChanged; 

     /// <summary> 
     ///  Handles the EventArrived event of the _deviceWatcher control. 
     /// </summary> 
     /// <param name="sender">The source of the event.</param> 
     /// <param name="e">The <see cref="EventArrivedEventArgs"/> instance containing the event data.</param> 
     private void _deviceWatcher_EventArrived(object sender, EventArrivedEventArgs e) 
     { 
      DiscoverArduinoDevices(); 
     } 

     /// <summary> 
     ///  Dynamically populates the SerialPorts property with relevant devices discovered from the WMI Win32_SerialPorts class. 
     /// </summary> 
     private void DiscoverArduinoDevices() 
     { 
      // Create a temporary dictionary to superimpose onto the SerialPorts property. 
      var dict = new Dictionary<string, SerialPort>(); 

      try 
      { 
       // Scan through each SerialPort registered in the WMI. 
       foreach (ManagementObject device in 
        new ManagementObjectSearcher("root\\CIMV2", "SELECT * FROM Win32_SerialPort").Get()) 
       { 
        // Ignore all devices that do not have a relevant VendorID. 
        if (!device["PNPDeviceID"].ToString().Contains("VID_2341") && // Arduino 
         !device["PNPDeviceID"].ToString().Contains("VID_04d0")) return; // Digi International (X-Bee) 

        // Create a SerialPort to add to the collection. 
        var port = new SerialPort(); 

        // Gather related configuration details for the Arduino Device. 
        var config = device.GetRelated("Win32_SerialPortConfiguration") 
             .Cast<ManagementObject>().ToList().FirstOrDefault(); 

        // Set the SerialPort's PortName property. 
        port.PortName = device["DeviceID"].ToString(); 

        // Set the SerialPort's BaudRate property. Use the devices maximum BaudRate as a fallback. 
        port.BaudRate = (config != null) 
             ? int.Parse(config["BaudRate"].ToString()) 
             : int.Parse(device["MaxBaudRate"].ToString()); 

        // Add the SerialPort to the dictionary. Key = Arduino device description. 
        dict.Add(device["Description"].ToString(), port); 
       } 

       // Return the dictionary. 
       SerialPorts = dict; 
      } 
      catch (ManagementException mex) 
      { 
       // Send a message to debug. 
       Debug.WriteLine(@"An error occurred while querying for WMI data: " + mex.Message); 
      } 
     } 

     /// <summary> 
     ///  Called when a property is set. 
     /// </summary> 
     /// <param name="propertyName">Name of the property.</param> 
     [NotifyPropertyChangedInvocator] 
     private void OnPropertyChanged([CallerMemberName] string propertyName = null) 
     { 
      var handler = PropertyChanged; 
      if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName)); 
     } 
    } 
} 

Answer 5

我發現我的Arduino納米的中國克隆在設備管理器中顯示正確的COM端口，但它並沒有在C＃應用程序村落下拉列表中顯示，當你使用這個嘗試，並得到所有端口命令：

using (var searcher = new ManagementObjectSearcher("SELECT * FROM WIN32_SerialPort")); 

但是，在執行時，它被正確地示出：

foreach (string z in SerialPort.GetPortNames()) 

所以，我有2所列出：一個具有第一碼輸出，以及一個從第二代碼輸出。比較兩者時，它會找到正確的COM端口。顯然，當使用原始Andurino Uno時，兩個命令都能正確顯示端口，所以這個解決方案只適用於中國克隆，由於某種奇怪的原因，這些克隆不可見using (var searcher = new ManagementObjectSearcher("SELECT * FROM WIN32_SerialPort"));

Answer 6

這種方法並不能幫助您找出arduino連接的端口到您的計算機

SerialPort.GetPortNames方法（）

// Get a list of serial port names. 
     string[] ports = SerialPort.GetPortNames(); 

     Console.WriteLine("The following serial ports were found:"); 
     Console.WriteLine("Aşşağıda Seri Bağlantı Noktaları Bulundu:");//For Turkish 
     // Display each port name to the console. 
     foreach(string port in ports) 
     { 
      Console.WriteLine(port); 
     } 

     Console.ReadLine();