Question

So far I have not been able to find an answer, but I wanted to know if there is a way, specifically with C#, to detect what the highest baudrate a serial port is capable of, without just having to test it.

Is there something in it’s hardware profile or something that stores the available baudrates for a certain port, that C# can query?

Answer 1

Using reflection you can/should do it like this:

   serialPort = new SerialPort(portName);
   serialPort.Open();
   object p = serialPort.BaseStream.GetType().GetField("commProp", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(serialPort.BaseStream);
   Int32 bv = (Int32)p.GetType().GetField("dwSettableBaud", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public).GetValue(p);

Note: The port will be opened in order to check it’s settable baudrate! 🙂

See this post for more information on how you can check the baudrate: How to programatically find all available Baudrates in C# (serialPort class)