Question

I’m using an Arduino with the Firmata library for communication to a C# application, and I want to eliminate a COM port configuration component since it can change from machine to machine…

Is it possible to:

1. Enumerate list of COM ports in the system? (In my googling I’ve seen some fairly ugly Win32 API code, hoping there’s maybe a cleaner version now)
2. Auto-detect which COM port(s) are connected to an Arduino?

Answer 1

This little bit of code has performed very well for this (returns the COM port string, i.e. “COM12” if Arduino is detected):

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;
        }