Class providing buffered UART communication functionality using separate circular buffer for send and receive channels. More...

#include <BufferedSerial.h>

Inheritance diagram for BufferedSerial:

Public Member Functions
	BufferedSerial (PinName tx, PinName rx, int baud=MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)
	Create a BufferedSerial port, connected to the specified transmit and receive pins, with a particular baud rate. More...

	BufferedSerial (const serial_pinmap_t &static_pinmap, int baud=MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)
	Create a BufferedSerial port, connected to the specified transmit and receive pins, with a particular baud rate. More...

short	poll (short events) const final
	Equivalent to POSIX poll(). More...

ssize_t	write (const void *buffer, size_t length) override
	Write the contents of a buffer to a file. More...

ssize_t	read (void *buffer, size_t length) override
	Read the contents of a file into a buffer. More...

int	close () override
	Close a file. More...

int	isatty () override
	Check if the file in an interactive terminal device. More...

off_t	seek (off_t offset, int whence) override
	Move the file position to a given offset from from a given location. More...

int	sync () override
	Flush any buffers associated with the file. More...

int	set_blocking (bool blocking) override
	Set blocking or non-blocking mode The default is blocking. More...

bool	is_blocking () const override
	Check current blocking or non-blocking mode for file operations. More...

int	enable_input (bool enabled) override
	Enable or disable input. More...

int	enable_output (bool enabled) override
	Enable or disable output. More...

void	sigio (Callback< void()> func) override
	Register a callback on state change of the file. More...

void	set_data_carrier_detect (PinName dcd_pin, bool active_high=false)
	Setup interrupt handler for DCD line. More...

void	set_baud (int baud)
	Set the baud rate. More...

void	set_format (int bits=8, Parity parity=BufferedSerial::None, int stop_bits=1)
	Set the transmission format used by the serial port. More...

void	set_flow_control (Flow type, PinName flow1=NC, PinName flow2=NC)
	Set the flow control type on the serial port. More...

bool	readable () const
	Definition depends on the subclass implementing FileHandle. More...

bool	writable () const
	Definition depends on the subclass implementing FileHandle. More...

virtual off_t	tell ()
	Get the file position of the file. More...

virtual void	rewind ()
	Rewind the file position to the beginning of the file. More...

virtual off_t	size ()
	Get the size of the file. More...

virtual int	truncate (off_t length)
	Truncate or extend a file. More...

Private Member Functions
int	readable ()
	Determine if there is a character available to read. More...

void	set_flow_control (Flow type, PinName flow1=NC, PinName flow2=NC)
	Set the flow control type on the serial port. More...

void	set_flow_control (Flow type, const serial_fc_pinmap_t &static_pinmap)
	Set the flow control type on the serial port. More...

int	write (const uint8_t *buffer, int length, const event_callback_t &callback, int event=SERIAL_EVENT_TX_COMPLETE)
	Begin asynchronous write using 8bit buffer. More...

int	write (const uint16_t *buffer, int length, const event_callback_t &callback, int event=SERIAL_EVENT_TX_COMPLETE)
	Begin asynchronous write using 16bit buffer. More...

int	read (uint8_t *buffer, int length, const event_callback_t &callback, int event=SERIAL_EVENT_RX_COMPLETE, unsigned char char_match=SERIAL_RESERVED_CHAR_MATCH)
	Begin asynchronous reading using 8bit buffer. More...

int	read (uint16_t *buffer, int length, const event_callback_t &callback, int event=SERIAL_EVENT_RX_COMPLETE, unsigned char char_match=SERIAL_RESERVED_CHAR_MATCH)
	Begin asynchronous reading using 16bit buffer. More...

Detailed Description

Class providing buffered UART communication functionality using separate circular buffer for send and receive channels.

Definition at line 52 of file BufferedSerial.h.

Constructor & Destructor Documentation

◆ BufferedSerial() [1/2]

BufferedSerial	(	PinName	tx,
		PinName	rx,
		int	baud = `MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE`
	)

Create a BufferedSerial port, connected to the specified transmit and receive pins, with a particular baud rate.

Parameters

tx	Transmit pin
rx	Receive pin
baud	The baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE, which is set via platform.default-serial-baud-rate in mbed_app.json)

◆ BufferedSerial() [2/2]

BufferedSerial	(	const serial_pinmap_t &	static_pinmap,
		int	baud = `MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE`
	)

Create a BufferedSerial port, connected to the specified transmit and receive pins, with a particular baud rate.

Parameters

static_pinmap	reference to structure which holds static pinmap
baud	The baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE, which is set via platform.default-serial-baud-rate in mbed_app.json)

Member Function Documentation

◆ poll()

short poll ( short events ) const

finalvirtual

Equivalent to POSIX poll().

Derived from FileHandle. Provides a mechanism to multiplex input/output over a set of file handles. The events that can be reported are POLLIN, POLLOUT, POLLHUP.

Reimplemented from FileHandle.

◆ write()

ssize_t write	(	const void *	buffer,
		size_t	length
	)

overridevirtual

Write the contents of a buffer to a file.

Follows POSIX semantics:

if blocking, block until all data is written
if no data can be written, and non-blocking set, return -EAGAIN
if some data can be written, and non-blocking set, write partial

Parameters

buffer	The buffer to write from
length	The number of bytes to write

Returns: The number of bytes written, negative error on failure

Implements FileHandle.

◆ read()

ssize_t read	(	void *	buffer,
		size_t	length
	)

overridevirtual

Read the contents of a file into a buffer.

Follows POSIX semantics:

if no data is available, and non-blocking set return -EAGAIN
if no data is available, and blocking set, wait until data is available
If any data is available, call returns immediately

Parameters

buffer	The buffer to read in to
length	The number of bytes to read

Returns: The number of bytes read, 0 at end of file, negative error on failure

Implements FileHandle.

◆ close()

int close ( )

overridevirtual

Close a file.

Returns: 0 on success, negative error code on failure

Implements FileHandle.

◆ isatty()

int isatty ( )

overridevirtual

Check if the file in an interactive terminal device.

Returns: True if the file is a terminal; False if the file is not a terminal; Negative error code on failure

Reimplemented from FileHandle.

◆ seek()

off_t seek	(	off_t	offset,
		int	whence
	)

overridevirtual

Move the file position to a given offset from from a given location.

Not valid for a device type FileHandle like BufferedSerial. In case of BufferedSerial, returns ESPIPE

Parameters

offset	The offset from whence to move to
whence	The start of where to seek SEEK_SET to start from beginning of file, SEEK_CUR to start from current position in file, SEEK_END to start from end of file

Returns: The new offset of the file, negative error code on failure

Implements FileHandle.

◆ sync()

int sync ( )

overridevirtual

Flush any buffers associated with the file.

Returns: 0 on success, negative error code on failure

Reimplemented from FileHandle.

◆ set_blocking()

int set_blocking ( bool blocking )

overridevirtual

Set blocking or non-blocking mode The default is blocking.

Parameters

blocking true for blocking mode, false for non-blocking mode.

Reimplemented from FileHandle.

Definition at line 170 of file BufferedSerial.h.

◆ is_blocking()

bool is_blocking ( ) const

overridevirtual

Check current blocking or non-blocking mode for file operations.

Returns: true for blocking mode, false for non-blocking mode.

Reimplemented from FileHandle.

Definition at line 180 of file BufferedSerial.h.

◆ enable_input()

int enable_input ( bool enabled )

overridevirtual

Enable or disable input.

Control enabling of device for input. This is primarily intended for temporary power-saving; the overall ability of the device to operate for input and/or output may be fixed at creation time, but this call can allow input to be temporarily disabled to permit power saving without losing device state.

Parameters

enabled true to enable input, false to disable.

Returns: 0 on success; Negative error code on failure

Reimplemented from FileHandle.

◆ enable_output()

int enable_output ( bool enabled )

overridevirtual

Enable or disable output.

Control enabling of device for output. This is primarily intended for temporary power-saving; the overall ability of the device to operate for input and/or output may be fixed at creation time, but this call can allow output to be temporarily disabled to permit power saving without losing device state.

Parameters

enabled true to enable output, false to disable.

Returns: 0 on success; Negative error code on failure

Reimplemented from FileHandle.

◆ sigio()

void sigio ( Callback< void()> func )

overridevirtual

Register a callback on state change of the file.

The specified callback will be called on state changes such as when the file can be written to or read from.

The callback may be called in an interrupt context and should not perform expensive operations.

Note! This is not intended as an attach-like asynchronous api, but rather as a building block for constructing such functionality.

The exact timing of when the registered function is called is not guaranteed and susceptible to change. It should be used as a cue to make read/write/poll calls to find the current state.

Parameters

func	Function to call on state change

Reimplemented from FileHandle.

◆ set_data_carrier_detect()

void set_data_carrier_detect	(	PinName	dcd_pin,
		bool	active_high = `false`
	)

Setup interrupt handler for DCD line.

If DCD line is connected, an IRQ handler will be setup. Does nothing if DCD is NC, i.e., not connected.

Parameters

dcd_pin	Pin-name for DCD
active_high	a boolean set to true if DCD polarity is active low

◆ set_baud()

void set_baud ( int baud )

Set the baud rate.

Parameters

baud	The baud rate

◆ set_format()

void set_format	(	int	bits = `8`,
		Parity	parity = `BufferedSerial::None`,
		int	stop_bits = `1`
	)

Set the transmission format used by the serial port.

Parameters

bits	The number of bits in a word (5-8; default = 8)
parity	The parity used (None, Odd, Even, Forced1, Forced0; default = None)
stop_bits	The number of stop bits (1 or 2; default = 1)

◆ set_flow_control()

void set_flow_control	(	Flow	type,
		PinName	flow1 = `NC`,
		PinName	flow2 = `NC`
	)

Set the flow control type on the serial port.

Parameters

type	the flow control type (Disabled, RTS, CTS, RTSCTS)
flow1	the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
flow2	the second flow control pin (CTS for RTSCTS)

◆ readable()

bool readable ( ) const

Definition depends on the subclass implementing FileHandle.

For example, if the FileHandle is of type Stream, readable() could return true when there is something available to read.

Returns: true when there is something available to read.

Definition at line 248 of file FileHandle.h.

◆ writable()

bool writable ( ) const

Definition depends on the subclass implementing FileHandle.

For example, if the FileHandle is of type Stream, writable() could return true when there is ample buffer space available for write() calls.

Returns: true if the FileHandle is writable.

Definition at line 237 of file FileHandle.h.

◆ tell()

virtual off_t tell ( )

virtualinherited

Get the file position of the file.

Note: This is equivalent to seek(0, SEEK_CUR)

Returns: The current offset in the file, negative error code on failure

Reimplemented in Stream, and File.

Definition at line 121 of file FileHandle.h.

◆ rewind()

virtual void rewind ( )

virtualinherited

Rewind the file position to the beginning of the file.

Note: This is equivalent to seek(0, SEEK_SET)

Reimplemented in Stream, and File.

Definition at line 130 of file FileHandle.h.

◆ size()

virtual off_t size ( )

virtualinherited

Get the size of the file.

Returns: Size of the file in bytes

Reimplemented in LocalFileHandle, Stream, File, SerialWireOutput, and UnbufferedSerial.

◆ truncate()

virtual int truncate ( off_t length )

virtualinherited

Truncate or extend a file.

The file's length is set to the specified value. The seek pointer is not changed. If the file is extended, the extended area appears as if it were zero-filled.

Parameters

length The requested new length for the file

Returns: Zero on success, negative error code on failure

Reimplemented in File.

Definition at line 151 of file FileHandle.h.

Public Member Functions

Private Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ BufferedSerial() [1/2]

◆ BufferedSerial() [2/2]

Member Function Documentation

◆ poll()

◆ write()

◆ read()

◆ close()

◆ isatty()

◆ seek()

◆ sync()

◆ set_blocking()

◆ is_blocking()

◆ enable_input()

◆ enable_output()

◆ sigio()

◆ set_data_carrier_detect()

◆ set_baud()

◆ set_format()

◆ set_flow_control()

◆ readable()

◆ writable()

◆ tell()

◆ rewind()

◆ size()

◆ truncate()