PropellerSession Class Reference

The PropellerSession class provides a persistent interface to Propeller hardware via PropellerManager. More...

#include <PropellerSession>

Inherits QObject.

Signals
void	bytesWritten (qint64 bytes)
void	readyRead ()
void	baudRateChanged (qint32 baudRate)
void	sendError (const QString &message)
void	deviceFree ()
void	deviceBusy ()

Public Member Functions
	PropellerSession (PropellerManager *manager, const QString &portname=QString(), QObject *parent=0)
	~PropellerSession ()
const QString &	portName ()
void	setPortName (const QString &name)
bool	isOpen ()
Access Control
bool	reserve ()
bool	isReserved ()
void	release ()
void	pause ()
bool	isPaused ()
void	unpause ()
Device I/O
bool	clear ()
bool	setBaudRate (quint32 baudRate)
qint64	bytesToWrite ()
qint64	bytesAvailable ()
QByteArray	read (qint64 maxSize)
QByteArray	readAll ()
bool	putChar (char c)
qint64	write (const QByteArray &byteArray)
int	error ()
QString	errorString ()
Download-Related
void	useReset (const QString &name, int pin)
void	useDefaultReset ()
bool	reset ()
quint32	resetPeriod ()
quint32	minimumTimeout ()
void	setMinimumTimeout (quint32 milliseconds)
quint32	calculateTimeout (quint32 bytes)

Detailed Description

The PropellerSession class provides a persistent interface to Propeller hardware via PropellerManager.

Sessions can communicate with any available device without needing to manually open and close ports. Many sessions can be connected to a single device at a time. However, sessions may also request exclusive access to a device to complete a long-running operation.

Usage

Using PropellerSession is easy because it handles all of the device setup transparently. In just a few lines of code, you'll be able to develop Propeller-based applications.

Here is a random function that writes some data to the device.

void writeToDevice()
{
    PropellerManager manager;
    PropellerSession session(&manager);
    session.setPortName("ttyUSB0");
    session.write(QByteArray("some data!"))
}

PropellerSession automatically disconnects from PropellerManager when destroyed, so manual cleanup isn't needed, and it's easy to make sure your connected devices don't end up in an invalid state.

See also

PropellerManager

Constructor & Destructor Documentation

PropellerSession::PropellerSession	(	PropellerManager *	manager,
		const QString &	portname = QString(),
		QObject *	parent = 0
	)

PropellerSession::~PropellerSession

(

)

Member Function Documentation

void PropellerSession::baudRateChanged ( qint32  baudRate )

signal

This signal is emitted after the baud rate has been changed. The new baud rate is passed as baudRate.

qint64 PropellerSession::bytesAvailable

(

)

Returns the number of bytes waiting to be read from the device.

This function returns 0 if the device is busy.

qint64 PropellerSession::bytesToWrite

(

)

Returns the number of bytes waiting to be written to the device.

This function returns 0 if the device is busy.

void PropellerSession::bytesWritten ( qint64  bytes )

signal

This signal is emitted once every time data has been written to the device. The bytes argument is the number of bytes that were written.

quint32 PropellerSession::calculateTimeout

(

quint32

bytes

)

Calculates a reasonable timeout value for writing the given number of bytes to the device.

Returns

the timeout value in milliseconds.

bool PropellerSession::clear

(

)

Clear send and receive buffers for this session.

void PropellerSession::deviceBusy ( )

signal

This signal is emitted when the device has been reserved by another session.

void PropellerSession::deviceFree ( )

signal

This signal is emitted when the device becomes free for use again.

int PropellerSession::error

(

)

Returns the error of the device.

Deprecated:

Errors are currently handled by PropellerDevice so this function is unlikely to return anything useful.

QString PropellerSession::errorString

(

)

Returns the error string of the device.

Deprecated:

Errors are currently handled by PropellerDevice so this function is unlikely to return anything useful.

bool PropellerSession::isOpen

(

)

Returns true if device is open, or false if not available or busy.

bool PropellerSession::isPaused

(

)

Returns true if session is paused, otherwise returns false.

bool PropellerSession::isReserved

(

)

Returns true if this session has reserved the device, otherwise false.

quint32 PropellerSession::minimumTimeout

(

)

Returns the minimum timeout for this device.

void PropellerSession::pause

(

)

Prevent session from sending or receiving data temporarily.

const QString & PropellerSession::portName

(

)

Returns the name of the current device.

bool PropellerSession::putChar

(

char

c

)

Writes a single byte of data to the device.

Returns

True if the command was successful, otherwise returns false.

QByteArray PropellerSession::read

(

qint64

maxSize

)

Reads the number of byte specified by maxSize from the device.

Returns

A QByteArray containing the data, or an empty one if no data was available or the device was not available.

QByteArray PropellerSession::readAll

(

)

Reads all of the available data from the device.

Returns

A QByteArray containing the data, or an empty one if there was no data or the device was not available.

void PropellerSession::readyRead ( )

signal

This signal is emitted every time new data is available for reading from the device.

void PropellerSession::release

(

)

Releases the device so that other sessions can use it.

bool PropellerSession::reserve

(

)

Reserve the device for exclusive access.

Returns

true if successfully reserved, otherwise false.

bool PropellerSession::reset

(

)

Reset the connected device.

Returns

true if successful, false if not found or busy.

quint32 PropellerSession::resetPeriod

(

)

void PropellerSession::sendError ( const QString &  message )

signal

bool PropellerSession::setBaudRate

(

quint32

baudRate

)

Set the baud rate of the device.

Note

This command can be used at any time, unlike some serial terminal implementations.

void PropellerSession::setMinimumTimeout

(

quint32

milliseconds

)

Sets the minimum timeout for this device.

void PropellerSession::setPortName

(

const QString &

name

)

Sets the name of the current device.

void PropellerSession::unpause

(

)

Resuming sending and receiving data.

void PropellerSession::useDefaultReset

(

)

Use the default reset strategy for this platform.

This command is not needed unless you have previously used useReset.

void PropellerSession::useReset	(	const QString &	name,
		int	pin
	)

Force the use of a specific reset strategy on this platform.

This function is usually not needed, but might be necessary if building PropellerManager for a platform that is not current supported.

qint64 PropellerSession::write

(

const QByteArray &

byteArray

)

Writes a QByteArray of data to the device.

Returns

The number of bytes written if successful, otherwise returns 0.