SoftwareSerial Class Reference

Software serial (UART) emulation on any pair of GPIO pins, driven by a timer interrupt. More...

#include <SoftwareSerial.h>

Inheritance diagram for SoftwareSerial:

Public Member Functions
	SoftwareSerial (pin_size_t receivePin, pin_size_t transmitPin, bool inverse_logic=false)
	Create a software serial instance on the given pins.
virtual	~SoftwareSerial ()
	Stop this instance: stop listening and disable its timer interrupt.
void	begin (long speed)
	Set the baud rate and initialize the pins.
bool	listen ()
	Set this instance as the listening one.
void	end ()
	Stop this instance: stop listening and disable the timer interrupt.
bool	isListening ()
	Check if this instance is the active listener.
bool	stopListening ()
	Stop listening on this instance.
bool	overflow ()
	Check whether a byte was dropped because the receive buffer was full.
int	peek ()
	Get the next received byte without removing it from the receive buffer.
virtual size_t	write (uint8_t byte)
	Send one byte.
virtual int	read ()
	Read the next byte from the receive buffer.
virtual int	available ()
	Get the number of bytes in the receive buffer.
virtual void	flush ()
	Clear the receive buffer and wait for any pending transmission to complete.
	operator bool ()
	Allow the instance to be used in a boolean context.

Static Public Member Functions
static void	setInterruptPriority (uint32_t preemptPriority, uint32_t subPriority)
	Set the priority of the timer interrupt shared by all software serial instances.

Detailed Description

Software serial (UART) emulation on any pair of GPIO pins, driven by a timer interrupt.

Note

When the receive and transmit pins are the same, the instance works in half-duplex mode.

Constructor & Destructor Documentation

SoftwareSerial()

SoftwareSerial::SoftwareSerial	(	pin_size_t	receivePin,
		pin_size_t	transmitPin,
		bool	inverse_logic = false
	)

Create a software serial instance on the given pins.

Parameters

receivePin	Pin used to receive data (RX).
transmitPin	Pin used to transmit data (TX). Use the same pin as receivePin for half-duplex mode.
inverse_logic	Optional, true to invert the logic level of the data. Default: false.

Member Function Documentation

available()

int SoftwareSerial::available ( )

virtual

Get the number of bytes in the receive buffer.

Returns

Number of bytes available to read.

begin()

void SoftwareSerial::begin

(

long

speed

)

Set the baud rate and initialize the pins.

Starts listening unless the instance is half-duplex.

Parameters

speed

Baud rate in bits per second. If FORCE_BAUD_RATE is defined, its value is used instead.

isListening()

bool SoftwareSerial::isListening ( )

inline

Check if this instance is the active listener.

Returns

true if this instance is listening, false otherwise.

listen()

bool SoftwareSerial::listen

(

)

Set this instance as the listening one.

Only one instance can listen at a time.

If another instance was listening, it is stopped and replaced by this one.

Returns

true if this instance became the listening one (replacing another one if any), false if it was already listening.

operator bool()

SoftwareSerial::operator bool ( )

inline

Allow the instance to be used in a boolean context.

Returns

Always true.

overflow()

bool SoftwareSerial::overflow ( )

inline

Check whether a byte was dropped because the receive buffer was full.

Clears the flag.

Returns

true if an overflow occurred since the last call, false otherwise.

peek()

int SoftwareSerial::peek

(

)

Get the next received byte without removing it from the receive buffer.

Returns

The next byte, or -1 if the receive buffer is empty.

read()

int SoftwareSerial::read ( )

virtual

Read the next byte from the receive buffer.

Returns

The byte read, or -1 if the receive buffer is empty.

setInterruptPriority()

void SoftwareSerial::setInterruptPriority ( uint32_t  preemptPriority, uint32_t  subPriority  )

static

Set the priority of the timer interrupt shared by all software serial instances.

Parameters

preemptPriority	Preemption priority of the interrupt.
subPriority	Sub-priority of the interrupt.

stopListening()

bool SoftwareSerial::stopListening

(

)

Stop listening on this instance.

Waits for any pending output to complete.

Returns

true if this instance was actually listening, false otherwise.

write()

size_t SoftwareSerial::write ( uint8_t  byte )

virtual

Send one byte.

Waits for any previous transmission to complete.

Parameters

byte	Byte to send.

Returns

Always 1.

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

• libraries/SoftwareSerial/src/SoftwareSerial.h
• libraries/SoftwareSerial/src/SoftwareSerial.cpp