Home Reference WMI Reference root CIMV2 Win32_SerialPortConfiguration


The Win32_SerialPortConfiguration class represents the default settings for data transmission on a Win32 serial port. this may include the default configuration for establishing a connection and error checking.

Quick Start


In this WMI class, all WMI properties are read-only. You can only read values but not change them.


Data type Boolean

The AbortReadWriteOnError property indicates whether read and write operations are terminated if an error occurs.

Values: $true or $false. If $true, the driver terminates all read and write operations with an error status if an error occurs. The driver will not accept any further communications operations until the application acknowledges the error.


Data type UInt32

The BaudRate property indicates the baud (bits per second) rate at which the communications device operates.

Example: 9600


Data type Boolean

The BinaryModeEnabled property indicates whether binary-mode data transfers are enabled for the serial port. Win32 systems only allow binary transfers through serial ports, so this value will always be $true.


Data type UInt32

The BitsPerByte property indicates the number of bits transmitted and received for each byte of data for the Win32 serial port. The number may vary with control and error correction bits, such as parity bits.

Example: 8


Data type String

A short textual description (one-line string) of the CIM_Setting object.


Data type Boolean

The ContinueXMitOnXOff property specifies whether data transmissions continue when the receiving buffer is close to full and an XoffChar character has been sent to the transmitter.

Values: $true or $false. If $true, transmission continues after the input buffer has come within XoffLim bytes of being full and the driver has transmitted the XoffChar character to stop receiving bytes. If $false, transmission does not continue until the input buffer is within XonLim bytes of being empty and the driver has transmitted the XonChar character to resume reception.


Data type Boolean

The CTSOutflowControl property determines whether the Clear To Send (CTS) is checked before transmitting data. CTS signals that both devices on the serial connection are ready to transfer data.

Values: $true or $false. If $true, data transmission is suspended until CTS signal is given.


Data type String

A textual description of the CIM_Setting object.


Data type Boolean

The DiscardNULLBytes property determines whether to discard NULL bytes (characters) when they are received.

Values: $true or $false. If $true, NULL bytes are discarded.


Data type Boolean

The DSROutflowControl property determines whether data outflow control is enabled when there is a Data Set Ready (DSR) condition. DSR signals that the connection has been established by the devices on the serial connection.

Values: $true or $false. If $true, DSR data transmission is suspended until DSR signal is given.


Data type Boolean

The DSRSensitivity property specifies whether the communications driver is sensitive to the state of the DSR signal.

Values: $true or $false. If $true, the driver ignores any bytes received, unless the DSR modem input line is high.


Data type String

The DTRFlowControlType property specifies the use of the data-terminal-ready (DTR) flow control after a connection has been established. After a communication line has been established the DTR can be left in the following states: enabled, to show that the connection is still active; disabled, to ignore the DTR once received; or it can be used as a data flow control flag.



Data type UInt32

The EOFCharacter property specifies the value of the character used to signal the end of data. .

Example: ^Z


Data type UInt32

The ErrorReplaceCharacter property specifies the value of the character used to replace bytes received with a parity error.

Example: ^C


Data type Boolean

The ErrorReplacementEnabled specifies whether bytes received with parity errors are replaced with the ErrorReplaceCharacter value. Characters with parity errors are only replaced if this member is $true and the parity is enabled.


Data type UInt32

The EventCharacter specifies the value of the control character that is used to signal an event, such as end of file.

Example: ^e


Data type Boolean

The IsBusy property determines whether the serial port is busy.

Values: $true or $false. If $true, the serial port is busy.


Data type String

The Name property indicates the name of the Win32 serial port.

Example: COM1


Data type String

The Parity property specifies the method of parity checking to be used. Parity is used as an error checking technique where an extra parity bit is included with every unit of data. If even parity is used, the parity bit is used to make the total count of bits set an even number. The receiver can then verify the validity of the data by counting the bits that are set. Odd parity, sets the parity bit so that the count of bits set is an odd number. Mark parity always leaves the parity bit set to 1, while space parity always leaves the parity bit set to 0.

Example: Even



Data type Boolean

The ParityCheckEnabled property determines whether parity checking is enabled.

Values: $true or $false. If $true, parity checking is enabled.


Data type UInt32


Data type String

The RTSFlowControlType property specifies the request-to-send (RTS) flow control. RTS is used to signal that data is available for transmission. Uses of this member include:

Disable – RTS is ignored after the first RTS signal is received.

Enable – RTS is left on for the data transfer session.

Handshake – RTS is turned off if the transmission buffer is more than three-quarters full, and RTS is turned on when the buffer is less than one-half full.

Toggle – RTS is turned on if there is any data buffered for transmission.



Data type String

The identifier by which the CIM_Setting object is known.


Data type String

The StopBits specifies the number of stop bits to be used. StopBits separate each unit of data on an asynchronous serial connection. They are also sent continuously when no data is available for transmission.

Example: 1



Data type UInt32

The XOffCharacter property specifies the value of the XOFF character for both transmission and reception. XOFF is a software control to stop the transmission of data (whereas RTS and CTS are hardware controls). XON resumes the transmission.


Data type UInt32

The XOffXMitThreshold property specifies the maximum number of bytes allowed in the input buffer before the XOFF character is sent.


Data type UInt32

The XOnCharacter property specifies the value of the XON character for both transmission and reception. XON is a software control to resume the transmission of data (whereas RTS and CTS are hardware controls). XOFF stops the transmission.


Data type UInt32

The XOnXMitThreshold property specifies the minimum number of bytes allowed in the input buffer before the XON character is sent. This member works in conjunction with XOffXMitThreshold to regulate the rate at which data is transferred.


Data type UInt32

The XOnXOffInFlowControl property specifies whether XON/XOFF flow control is used during reception.

Values $true or $false. If $true the XOffCharacter is sent when the input buffer comes within XOffXMitThreshold bytes of being full, and the XOnCharacter is sent when the input buffer comes within XOnXMitThreshold bytes of being empty.


Data type UInt32

The XOnXOffOutFlowControl specifies whether XON/XOFF flow control is used during transmission.

Values $true or $false. If $true, transmission stops when the XOffCharacter is received and starts again when the XonCharacter is received.



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Content last updated: 2013-12-27 12:27:00 (UTC).