SerialPort.BaudRate Property

Gets or sets the serial baud rate.

Namespace: System.IO.Ports
Assembly: System (in system.dll)

public int BaudRate { get; set; }
/** @property */
public int get_BaudRate ()

/** @property */
public void set_BaudRate (int value)

public function get BaudRate () : int

public function set BaudRate (value : int)

Not applicable.

Property Value

The baud rate.

Exception typeCondition


The baud rate specified is less than or equal to zero, or is greater than the maximum allowable baud rate for the device.


The port is in an invalid state.

- or -

An attempt to set the state of the underlying port failed. For example, the parameters passed from this SerialPort object were invalid.

The baud rate must be supported by the user's serial driver. The default value is 9600 bits per second (bps).

The following code example demonstrates the use of the SerialPort class to allow two users to chat from two separate computers connected by a null modem cable. In this example, the users are prompted for the port settings and a username before chatting. This code example is part of a larger code example provided for the SerialPort class.

public static void Main()
    string name;
    string message;
    StringComparer stringComparer = StringComparer.OrdinalIgnoreCase;
    Thread readThread = new Thread(Read);

    // Create a new SerialPort object with default settings.
    _serialPort = new SerialPort();

    // Allow the user to set the appropriate properties.
    _serialPort.PortName = SetPortName(_serialPort.PortName);
    _serialPort.BaudRate = SetPortBaudRate(_serialPort.BaudRate);
    _serialPort.Parity = SetPortParity(_serialPort.Parity);
    _serialPort.DataBits = SetPortDataBits(_serialPort.DataBits);
    _serialPort.StopBits = SetPortStopBits(_serialPort.StopBits);
    _serialPort.Handshake = SetPortHandshake(_serialPort.Handshake);

    // Set the read/write timeouts
    _serialPort.ReadTimeout = 500;
    _serialPort.WriteTimeout = 500;

    _continue = true;

    Console.Write("Name: ");
    name = Console.ReadLine();

    Console.WriteLine("Type QUIT to exit");

    while (_continue)
        message = Console.ReadLine();

        if (stringComparer.Equals("quit", message))
            _continue = false;
                String.Format("<{0}>: {1}", name, message) );


public static void Read()
    while (_continue)
            string message = _serialPort.ReadLine();
        catch (TimeoutException) { }

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0

.NET Compact Framework

Supported in: 2.0