Driver for the RS-232 serial port on the roboRIO. More...

#include <wpi/hardware/bus/SerialPort.hpp>

Public Types
enum class	Port { ONBOARD = 0 , MXP = 1 , USB = 2 , USB_1 = 2 , USB_2 = 3 }
	Serial port. More...
enum class	Parity { NONE = 0 , ODD = 1 , EVEN = 2 , MARK = 3 , SPACE = 4 }
	Represents the parity to use for serial communications. More...
enum class	StopBits { ONE = 10 , ONE_POINT_FIVE = 15 , TWO = 20 }
	Represents the number of stop bits to use for Serial Communication. More...
enum class	FlowControl { NONE = 0 , XON_XOFF = 1 , RTS_CTS = 2 , DTR_DSR = 4 }
	Represents what type of flow control to use for serial communication. More...
enum class	WriteBufferMode { FLUSH_ON_ACCESS = 1 , FLUSH_WHEN_FULL = 2 }
	Represents which type of buffer mode to use when writing to a serial port. More...

Public Member Functions
	SerialPort (int baudRate, Port port=Port::ONBOARD, int dataBits=8, Parity parity=Parity::NONE, StopBits stopBits=StopBits::ONE)
	Create an instance of a Serial Port class.
	SerialPort (int baudRate, std::string_view portName, Port port=Port::ONBOARD, int dataBits=8, Parity parity=Parity::NONE, StopBits stopBits=StopBits::ONE)
	Create an instance of a Serial Port class.
	SerialPort (SerialPort &&rhs)=default
SerialPort &	operator= (SerialPort &&rhs)=default
void	SetFlowControl (FlowControl flowControl)
	Set the type of flow control to enable on this port.
void	EnableTermination (char terminator='\n')
	Enable termination and specify the termination character.
void	DisableTermination ()
	Disable termination behavior.
int	GetBytesReceived ()
	Get the number of bytes currently available to read from the serial port.
int	Read (char *buffer, int count)
	Read raw bytes out of the buffer.
int	Write (const char *buffer, int count)
	Write raw bytes to the buffer.
int	Write (std::string_view buffer)
	Write raw bytes to the buffer.
void	SetTimeout (wpi::units::second_t timeout)
	Configure the timeout of the serial port.
void	SetReadBufferSize (int size)
	Specify the size of the input buffer.
void	SetWriteBufferSize (int size)
	Specify the size of the output buffer.
void	SetWriteBufferMode (WriteBufferMode mode)
	Specify the flushing behavior of the output buffer.
void	Flush ()
	Force the output buffer to be written to the port.
void	Reset ()
	Reset the serial port driver to a known state.

Detailed Description

Driver for the RS-232 serial port on the roboRIO.

The current implementation uses the VISA formatted I/O mode. This means that all traffic goes through the formatted buffers. This allows the intermingled use of Printf(), Scanf(), and the raw buffer accessors Read() and Write().

More information can be found in the NI-VISA User Manual here: http://www.ni.com/pdf/manuals/370423a.pdf and the NI-VISA Programmer's Reference Manual here: http://www.ni.com/pdf/manuals/370132c.pdf

Member Enumeration Documentation

◆ FlowControl

enum class wpi::SerialPort::FlowControl

strong

Represents what type of flow control to use for serial communication.

Enumerator
NONE	No flow control.
XON_XOFF	XON/XOFF flow control.
RTS_CTS	RTS/CTS flow control.
DTR_DSR	DTS/DSR flow control.

◆ Parity

enum class wpi::SerialPort::Parity

strong

Represents the parity to use for serial communications.

Enumerator
NONE	No parity.
ODD	Odd parity.
EVEN	Even parity.
MARK	Parity bit always on.
SPACE	Parity bit always off.

◆ Port

enum class wpi::SerialPort::Port

strong

Serial port.

Enumerator
ONBOARD	Onboard serial port on the roboRIO.
MXP	MXP (roboRIO MXP) serial port.
USB	USB serial port (same as USB_1).
USB_1	USB serial port 1.
USB_2	USB serial port 2.

◆ StopBits

enum class wpi::SerialPort::StopBits

strong

Represents the number of stop bits to use for Serial Communication.

Enumerator
ONE	One stop bit.
ONE_POINT_FIVE	One and a half stop bits.
TWO	Two stop bits.

◆ WriteBufferMode

enum class wpi::SerialPort::WriteBufferMode

strong

Represents which type of buffer mode to use when writing to a serial port.

Enumerator
FLUSH_ON_ACCESS	Flush the buffer on each access.
FLUSH_WHEN_FULL	Flush the buffer when it is full.

Constructor & Destructor Documentation

◆ SerialPort() [1/3]

wpi::SerialPort::SerialPort	(	int	baudRate,
		Port	port = Port::ONBOARD,
		int	dataBits = 8,
		Parity	parity = Parity::NONE,
		StopBits	stopBits = StopBits::ONE )

explicit

Create an instance of a Serial Port class.

Parameters

baudRate	The baud rate to configure the serial port.
port	The physical port to use
dataBits	The number of data bits per transfer. Valid values are between 5 and 8 bits.
parity	Select the type of parity checking to use.
stopBits	The number of stop bits to use as defined by the enum StopBits.

◆ SerialPort() [2/3]

wpi::SerialPort::SerialPort	(	int	baudRate,
		std::string_view	portName,
		Port	port = Port::ONBOARD,
		int	dataBits = 8,
		Parity	parity = Parity::NONE,
		StopBits	stopBits = StopBits::ONE )

Create an instance of a Serial Port class.

Prefer to use the constructor that doesn't take a port name, but in some cases the automatic detection might not work correctly.

Parameters

baudRate	The baud rate to configure the serial port.
port	The physical port to use
portName	The direct port name to use
dataBits	The number of data bits per transfer. Valid values are between 5 and 8 bits.
parity	Select the type of parity checking to use.
stopBits	The number of stop bits to use as defined by the enum StopBits.

◆ SerialPort() [3/3]

wpi::SerialPort::SerialPort ( SerialPort && rhs )

default

Member Function Documentation

◆ DisableTermination()

void wpi::SerialPort::DisableTermination ( )

Disable termination behavior.

◆ EnableTermination()

void wpi::SerialPort::EnableTermination ( char terminator = '\n' )

Enable termination and specify the termination character.

Termination is currently only implemented for receive. When the the terminator is received, the Read() or Scanf() will return fewer bytes than requested, stopping after the terminator.

Parameters

terminator The character to use for termination.

◆ Flush()

void wpi::SerialPort::Flush ( )

Force the output buffer to be written to the port.

This is used when SetWriteBufferMode() is set to FLUSH_WHEN_FULL to force a flush before the buffer is full.

◆ GetBytesReceived()

int wpi::SerialPort::GetBytesReceived ( )

Get the number of bytes currently available to read from the serial port.

Returns: The number of bytes available to read

◆ operator=()

SerialPort & wpi::SerialPort::operator= ( SerialPort && rhs )

default

◆ Read()

int wpi::SerialPort::Read	(	char *	buffer,
		int	count )

Read raw bytes out of the buffer.

Parameters

buffer	Pointer to the buffer to store the bytes in.
count	The maximum number of bytes to read.

Returns: The number of bytes actually read into the buffer.

◆ Reset()

void wpi::SerialPort::Reset ( )

Reset the serial port driver to a known state.

Empty the transmit and receive buffers in the device and formatted I/O.

◆ SetFlowControl()

void wpi::SerialPort::SetFlowControl ( FlowControl flowControl )

Set the type of flow control to enable on this port.

By default, flow control is disabled.

◆ SetReadBufferSize()

void wpi::SerialPort::SetReadBufferSize ( int size )

Specify the size of the input buffer.

Specify the amount of data that can be stored before data from the device is returned to Read or Scanf. If you want data that is received to be returned immediately, set this to 1.

It the buffer is not filled before the read timeout expires, all data that has been received so far will be returned.

Parameters

size	The read buffer size.

◆ SetTimeout()

void wpi::SerialPort::SetTimeout ( wpi::units::second_t timeout )

Configure the timeout of the serial port.

This defines the timeout for transactions with the hardware. It will affect reads and very large writes.

Parameters

timeout The time to wait for I/O.

◆ SetWriteBufferMode()

void wpi::SerialPort::SetWriteBufferMode ( WriteBufferMode mode )

Specify the flushing behavior of the output buffer.

When set to FLUSH_ON_ACCESS, data is synchronously written to the serial port after each call to either Printf() or Write().

When set to FLUSH_WHEN_FULL, data will only be written to the serial port when the buffer is full or when Flush() is called.

Parameters

mode	The write buffer mode.

◆ SetWriteBufferSize()

void wpi::SerialPort::SetWriteBufferSize ( int size )

Specify the size of the output buffer.

Specify the amount of data that can be stored before being transmitted to the device.

Parameters

size	The write buffer size.

◆ Write() [1/2]

int wpi::SerialPort::Write	(	const char *	buffer,
		int	count )

Write raw bytes to the buffer.

Parameters

buffer	Pointer to the buffer to read the bytes from.
count	The maximum number of bytes to write.

Returns: The number of bytes actually written into the port.

◆ Write() [2/2]

int wpi::SerialPort::Write ( std::string_view buffer )

Write raw bytes to the buffer.

Use Write({data, len}) to get a buffer that is shorter than the length of the string.

Parameters

buffer the buffer to read the bytes from.

Returns: The number of bytes actually written into the port.

The documentation for this class was generated from the following file:

wpi/hardware/bus/SerialPort.hpp

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ FlowControl

◆ Parity

◆ Port

◆ StopBits

◆ WriteBufferMode

Constructor & Destructor Documentation

◆ SerialPort() [1/3]

◆ SerialPort() [2/3]

◆ SerialPort() [3/3]

Member Function Documentation

◆ DisableTermination()

◆ EnableTermination()

◆ Flush()

◆ GetBytesReceived()

◆ operator=()

◆ Read()

◆ Reset()

◆ SetFlowControl()

◆ SetReadBufferSize()

◆ SetTimeout()

◆ SetWriteBufferMode()

◆ SetWriteBufferSize()

◆ Write() [1/2]

◆ Write() [2/2]