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Public Member Functions | Private Member Functions
UARTSerial Class Reference

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

#include <UARTSerial.h>

Inheritance diagram for UARTSerial:
SerialBase FileHandle NonCopyable< UARTSerial > NonCopyable< FileHandle >

Public Member Functions

 UARTSerial (PinName tx, PinName rx, int baud=MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)
 Create a UARTSerial port, connected to the specified transmit and receive pins, with a particular baud rate. More...
 
virtual short poll (short events) const
 Equivalent to POSIX poll(). More...
 
virtual ssize_t write (const void *buffer, size_t length)
 Write the contents of a buffer to a file. More...
 
virtual ssize_t read (void *buffer, size_t length)
 Read the contents of a file into a buffer. More...
 
virtual int close ()
 Close a file. More...
 
virtual int isatty ()
 Check if the file in an interactive terminal device. More...
 
virtual off_t seek (off_t offset, int whence)
 Move the file position to a given offset from from a given location. More...
 
virtual int sync ()
 Flush any buffers associated with the file. More...
 
virtual int set_blocking (bool blocking)
 Set blocking or non-blocking mode The default is blocking. More...
 
virtual bool is_blocking () const
 Check current blocking or non-blocking mode for file operations. More...
 
virtual void sigio (Callback< void()> func)
 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=UARTSerial::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...
 
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 off_t lseek (off_t offset, int whence)
 Move the file position to a given offset from a given location. More...
 
virtual int fsync ()
 Flush any buffers associated with the FileHandle, ensuring it is up to date on disk. More...
 
virtual off_t flen ()
 Find the length of the file. More...
 
bool writable () const
 Definition depends on the subclass implementing FileHandle. More...
 
bool readable () const
 Definition depends on the subclass implementing FileHandle. More...
 

Private Member Functions

void baud (int baudrate)
 Set the baud rate of the serial port. More...
 
void format (int bits=8, Parity parity=SerialBase::None, int stop_bits=1)
 Set the transmission format used by the serial port. More...
 
int readable ()
 Determine if there is a character available to read. More...
 
int writeable ()
 Determine if there is space available to write a character. More...
 
void attach (Callback< void()> func, IrqType type=RxIrq)
 Attach a function to call whenever a serial interrupt is generated. More...
 
template<typename T >
void attach (T *obj, void(T::*method)(), IrqType type=RxIrq)
 Attach a member function to call whenever a serial interrupt is generated. More...
 
template<typename T >
void attach (T *obj, void(*method)(T *), IrqType type=RxIrq)
 Attach a member function to call whenever a serial interrupt is generated. More...
 
void set_break ()
 Generate a break condition on the serial line NOTE: Clear break needs to run at least one frame after set_break is called. More...
 
void clear_break ()
 Clear a break condition on the serial line NOTE: Should be run at least one frame after set_break is called. More...
 
void send_break ()
 Generate a break condition on the serial line. 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...
 
void abort_write ()
 Abort the on-going write transfer. 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...
 
void abort_read ()
 Abort the on-going read transfer. More...
 
int set_dma_usage_tx (DMAUsage usage)
 Configure DMA usage suggestion for non-blocking TX transfers. More...
 
int set_dma_usage_rx (DMAUsage usage)
 Configure DMA usage suggestion for non-blocking RX transfers. More...
 

Detailed Description

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

Definition at line 50 of file UARTSerial.h.

Constructor & Destructor Documentation

UARTSerial ( PinName  tx,
PinName  rx,
int  baud = MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE 
)

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

Parameters
txTransmit pin
rxReceive pin
baudThe baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)

Member Function Documentation

virtual int close ( )
virtual

Close a file.

Returns
0 on success, negative error code on failure

Implements FileHandle.

virtual off_t flen ( )
virtualinherited

Find the length of the file.

Returns
Length of the file
Deprecated:
Replaced by `off_t FileHandle::size()'

Definition at line 180 of file FileHandle.h.

virtual int fsync ( )
virtualinherited

Flush any buffers associated with the FileHandle, ensuring it is up to date on disk.

Returns
0 on success or un-needed, -1 on error
Deprecated:
Replaced by `int FileHandle::sync()'

Definition at line 168 of file FileHandle.h.

virtual bool is_blocking ( ) const
virtual

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 150 of file UARTSerial.h.

virtual int isatty ( )
virtual

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.

virtual off_t lseek ( off_t  offset,
int  whence 
)
virtualinherited

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

Parameters
offsetThe offset from whence to move to
whenceSEEK_SET for the start of the file, SEEK_CUR for the current file position, or SEEK_END for the end of the file.
Returns
new file position on success, -1 on failure or unsupported
Deprecated:
Replaced by `off_t FileHandle::seek(off_t offset, int whence = SEEK_SET)'

Definition at line 154 of file FileHandle.h.

virtual short poll ( short  events) const
virtual

Equivalent to POSIX poll().

Derived from FileHandle. Provides a mechanism to multiplex input/output over a set of file handles.

Reimplemented from FileHandle.

virtual ssize_t read ( void *  buffer,
size_t  length 
)
virtual

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
bufferThe buffer to read in to
lengthThe number of bytes to read
Returns
The number of bytes read, 0 at end of file, negative error on failure

Implements FileHandle.

bool readable ( ) const
inherited

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 241 of file FileHandle.h.

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 File, and Stream.

Definition at line 130 of file FileHandle.h.

virtual off_t seek ( off_t  offset,
int  whence 
)
virtual

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

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

Parameters
offsetThe offset from whence to move to
whenceThe 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.

void set_baud ( int  baud)

Set the baud rate.

Parameters
baudThe baud rate
virtual int set_blocking ( bool  blocking)
virtual

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

Parameters
blockingtrue for blocking mode, false for non-blocking mode.

Reimplemented from FileHandle.

Definition at line 140 of file UARTSerial.h.

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_pinPin-name for DCD
active_higha boolean set to true if DCD polarity is active low
void set_flow_control ( Flow  type,
PinName  flow1 = NC,
PinName  flow2 = NC 
)

Set the flow control type on the serial port.

Parameters
typethe flow control type (Disabled, RTS, CTS, RTSCTS)
flow1the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
flow2the second flow control pin (CTS for RTSCTS)
void set_format ( int  bits = 8,
Parity  parity = UARTSerial::None,
int  stop_bits = 1 
)

Set the transmission format used by the serial port.

Parameters
bitsThe number of bits in a word (5-8; default = 8)
parityThe parity used (None, Odd, Even, Forced1, Forced0; default = None)
stop_bitsThe number of stop bits (1 or 2; default = 1)
virtual void sigio ( Callback< void()>  func)
virtual

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
funcFunction to call on state change

Reimplemented from FileHandle.

virtual off_t size ( )
virtualinherited

Get the size of the file.

Returns
Size of the file in bytes

Reimplemented in File, Stream, and SerialWireOutput.

virtual int sync ( )
virtual

Flush any buffers associated with the file.

Returns
0 on success, negative error code on failure

Reimplemented from FileHandle.

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 File, and Stream.

Definition at line 121 of file FileHandle.h.

bool writable ( ) const
inherited

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 230 of file FileHandle.h.

virtual ssize_t write ( const void *  buffer,
size_t  length 
)
virtual

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
    bufferThe buffer to write from
    lengthThe number of bytes to write
    Returns
    The number of bytes written, negative error on failure

Implements FileHandle.

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