Qt Serial Port Baud Rate

Qt Serial Port Baud Rate Rating: 7,3/10 8411 reviews
Serial
  1. Baud Rate Serial Port

Baud Rate Serial Port

Baud

Issue with serial communication with. The serial error which i get when i connect with baud rate. If you are running Raspbian or similar then the UART will be used as a serial console. Using a suitable cable, such as the TTL-232R-3V3-WE, you can connect it to your PC and using some simple terminal software set to 115200-8-N-1 use the command line interface to the Raspberry Pi in the same way as if you we're using a keyboard and.

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Qt Serial Port Baud Rate
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/****************************************************************************
**
** Copyright (C) 2012 Denis Shienkov <denis.shienkov@gmail.com>
** Copyright (C) 2012 Laszlo Papp <lpapp@kde.org>
** Copyright (C) 2012 Andre Hartmann <aha_1980@gmx.de>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtSerialPort module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include'qserialport_p.h'
#include'qserialportinfo_p.h'
#include<QtCore/qelapsedtimer.h>
#include<QtCore/qmap.h>
#include<QtCore/qsocketnotifier.h>
#include<QtCore/qstandardpaths.h>
#include<private/qcore_unix_p.h>
#include<errno.h>
#include<fcntl.h>
#include<sys/ioctl.h>
#include<sys/time.h>
#include<unistd.h>
#ifdef Q_OS_OSX
#if defined(MAC_OS_X_VERSION_10_4) && (MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_4)
#include<IOKit/serial/ioss.h>
#endif
#endif
#ifdef Q_OS_QNX
#defineCRTSCTS (IHFLOW OHFLOW)
#endif
#ifdef Q_OS_LINUX
# ifdef Q_OS_ANDROID
# include<android/api-level.h>
# else
# define__ANDROID_API__21
# endif
# if !defined(Q_OS_ANDROID) (!defined(Q_PROCESSOR_X86) && __ANDROID_API__ < 21)
structtermios2 {
tcflag_t c_iflag; /* input mode flags */
tcflag_t c_oflag; /* output mode flags */
tcflag_t c_cflag; /* control mode flags */
tcflag_t c_lflag; /* local mode flags */
cc_t c_line; /* line discipline */
cc_t c_cc[19]; /* control characters */
speed_t c_ispeed; /* input speed */
speed_t c_ospeed; /* output speed */
};
# endif
#ifndef TCGETS2
#defineTCGETS2_IOR('T', 0x2A, structtermios2)
#endif
#ifndef TCSETS2
#defineTCSETS2_IOW('T', 0x2B, structtermios2)
#endif
#ifndef BOTHER
#defineBOTHER0010000
#endif
#endif
QT_BEGIN_NAMESPACE
QString serialPortLockFilePath(const QString &portName)
{
staticconst QStringList lockDirectoryPaths = QStringList()
<< QStringLiteral('/var/lock')
<< QStringLiteral('/etc/locks')
<< QStringLiteral('/var/spool/locks')
<< QStringLiteral('/var/spool/uucp')
<< QStringLiteral('/tmp')
<< QStringLiteral('/var/tmp')
<< QStringLiteral('/var/lock/lockdev')
<< QStringLiteral('/run/lock')
#ifdef Q_OS_ANDROID
<< QStringLiteral('/data/local/tmp')
#endif
<< QStandardPaths::writableLocation(QStandardPaths::TempLocation);
QString fileName = portName;
fileName.replace(QLatin1Char('/'), QLatin1Char('_'));
fileName.prepend(QLatin1String('/LCK.'));
QString lockFilePath;
for (const QString &lockDirectoryPath : lockDirectoryPaths) {
const QString filePath = lockDirectoryPath + fileName;
QFileInfo lockDirectoryInfo(lockDirectoryPath);
if (lockDirectoryInfo.isReadable()) {
if (QFile::exists(filePath) lockDirectoryInfo.isWritable()) {
lockFilePath = filePath;
break;
}
}
}
if (lockFilePath.isEmpty()) {
qWarning('The following directories are not readable or writable for detaling with lock filesn');
for (const QString &lockDirectoryPath : lockDirectoryPaths)
qWarning('t%sn', qPrintable(lockDirectoryPath));
returnQString();
}
return lockFilePath;
}
classReadNotifier : publicQSocketNotifier
{
public:
explicitReadNotifier(QSerialPortPrivate *d, QObject *parent)
: QSocketNotifier(d->descriptor, QSocketNotifier::Read, parent)
, dptr(d)
{
}
protected:
boolevent(QEvent *e) Q_DECL_OVERRIDE
{
if (e->type() QEvent::SockAct) {
dptr->readNotification();
returntrue;
}
returnQSocketNotifier::event(e);
}
private:
QSerialPortPrivate * const dptr;
};
classWriteNotifier : publicQSocketNotifier
{
public:
explicitWriteNotifier(QSerialPortPrivate *d, QObject *parent)
: QSocketNotifier(d->descriptor, QSocketNotifier::Write, parent)
, dptr(d)
{
}
protected:
boolevent(QEvent *e) Q_DECL_OVERRIDE
{
if (e->type() QEvent::SockAct) {
dptr->completeAsyncWrite();
returntrue;
}
returnQSocketNotifier::event(e);
}
private:
QSerialPortPrivate * const dptr;
};
staticinlinevoidqt_set_common_props(termios *tio, QIODevice::OpenMode m)
{
#ifdef Q_OS_SOLARIS
tio->c_iflag &= ~(IMAXBEL IGNBRK BRKINT PARMRK ISTRIP INLCR IGNCR ICRNL IXON);
tio->c_oflag &= ~OPOST;
tio->c_lflag &= ~(ECHO ECHONL ICANON ISIG IEXTEN);
tio->c_cflag &= ~(CSIZE PARENB);
tio->c_cflag = CS8;
#else
::cfmakeraw(tio);
#endif
tio->c_cflag = CLOCAL;
tio->c_cc[VTIME] = 0;
tio->c_cc[VMIN] = 0;
if (m & QIODevice::ReadOnly)
tio->c_cflag = CREAD;
}
staticinlinevoidqt_set_databits(termios *tio, QSerialPort::DataBits databits)
{
tio->c_cflag &= ~CSIZE;
switch (databits) {
case QSerialPort::Data5:
tio->c_cflag = CS5;
break;
case QSerialPort::Data6:
tio->c_cflag = CS6;
break;
case QSerialPort::Data7:
tio->c_cflag = CS7;
break;
case QSerialPort::Data8:
tio->c_cflag = CS8;
break;
default:
tio->c_cflag = CS8;
break;
}
}
staticinlinevoidqt_set_parity(termios *tio, QSerialPort::Parity parity)
{
tio->c_iflag &= ~(PARMRK INPCK);
tio->c_iflag = IGNPAR;
switch (parity) {
#ifdef CMSPAR
// Here Installation parity only for GNU/Linux where the macro CMSPAR.
case QSerialPort::SpaceParity:
tio->c_cflag &= ~PARODD;
tio->c_cflag = PARENB CMSPAR;
break;
case QSerialPort::MarkParity:
tio->c_cflag = PARENB CMSPAR PARODD;
break;
#endif
case QSerialPort::NoParity:
tio->c_cflag &= ~PARENB;
break;
case QSerialPort::EvenParity:
tio->c_cflag &= ~PARODD;
tio->c_cflag = PARENB;
break;
case QSerialPort::OddParity:
tio->c_cflag = PARENB PARODD;
break;
default:
tio->c_cflag = PARENB;
tio->c_iflag = PARMRK INPCK;
tio->c_iflag &= ~IGNPAR;
break;
}
}
staticinlinevoidqt_set_stopbits(termios *tio, QSerialPort::StopBits stopbits)
{
switch (stopbits) {
case QSerialPort::OneStop:
tio->c_cflag &= ~CSTOPB;
break;
case QSerialPort::TwoStop:
tio->c_cflag = CSTOPB;
break;
default:
tio->c_cflag &= ~CSTOPB;
break;
}
}
staticinlinevoidqt_set_flowcontrol(termios *tio, QSerialPort::FlowControl flowcontrol)
{
switch (flowcontrol) {
case QSerialPort::NoFlowControl:
tio->c_cflag &= ~CRTSCTS;
tio->c_iflag &= ~(IXON IXOFF IXANY);
break;
case QSerialPort::HardwareControl:
tio->c_cflag = CRTSCTS;
tio->c_iflag &= ~(IXON IXOFF IXANY);
break;
case QSerialPort::SoftwareControl:
tio->c_cflag &= ~CRTSCTS;
tio->c_iflag = IXON IXOFF IXANY;
break;
default:
tio->c_cflag &= ~CRTSCTS;
tio->c_iflag &= ~(IXON IXOFF IXANY);
break;
}
}
boolQSerialPortPrivate::open(QIODevice::OpenMode mode)
{
QString lockFilePath = serialPortLockFilePath(QSerialPortInfoPrivate::portNameFromSystemLocation(systemLocation));
bool isLockFileEmpty = lockFilePath.isEmpty();
if (isLockFileEmpty) {
qWarning('Failed to create a lock file for opening the device');
setError(QSerialPortErrorInfo(QSerialPort::PermissionError, QSerialPort::tr('Permission error while creating lock file')));
returnfalse;
}
QScopedPointer<QLockFile> newLockFileScopedPointer(newQLockFile(lockFilePath));
if (!newLockFileScopedPointer->tryLock()) {
setError(QSerialPortErrorInfo(QSerialPort::PermissionError, QSerialPort::tr('Permission error while locking the device')));
returnfalse;
}
int flags = O_NOCTTY O_NONBLOCK;
switch (mode & QIODevice::ReadWrite) {
case QIODevice::WriteOnly:
flags = O_WRONLY;
break;
case QIODevice::ReadWrite:
flags = O_RDWR;
break;
default:
flags = O_RDONLY;
break;
}
descriptor = qt_safe_open(systemLocation.toLocal8Bit().constData(), flags);
if (descriptor -1) {
setError(getSystemError());
returnfalse;
}
if (!initialize(mode)) {
qt_safe_close(descriptor);
returnfalse;
}
lockFileScopedPointer.swap(newLockFileScopedPointer);
returntrue;
}
voidQSerialPortPrivate::close()
{
if (settingsRestoredOnClose)
::tcsetattr(descriptor, TCSANOW, &restoredTermios);
#ifdef TIOCNXCL
::ioctl(descriptor, TIOCNXCL);
#endif
delete readNotifier;
readNotifier = nullptr;
delete writeNotifier;
writeNotifier = nullptr;
qt_safe_close(descriptor);
lockFileScopedPointer.reset(nullptr);
descriptor = -1;
pendingBytesWritten = 0;
writeSequenceStarted = false;
}
QSerialPort::PinoutSignals QSerialPortPrivate::pinoutSignals()
{
int arg = 0;
if (::ioctl(descriptor, TIOCMGET, &arg) -1) {
setError(getSystemError());
return QSerialPort::NoSignal;
}
QSerialPort::PinoutSignals ret = QSerialPort::NoSignal;
#ifdef TIOCM_LE
if (arg & TIOCM_LE)
ret = QSerialPort::DataSetReadySignal;
#endif
#ifdef TIOCM_DTR
if (arg & TIOCM_DTR)
ret = QSerialPort::DataTerminalReadySignal;
#endif
#ifdef TIOCM_RTS
if (arg & TIOCM_RTS)
ret = QSerialPort::RequestToSendSignal;
#endif
#ifdef TIOCM_ST
if (arg & TIOCM_ST)
ret = QSerialPort::SecondaryTransmittedDataSignal;
#endif
#ifdef TIOCM_SR
if (arg & TIOCM_SR)
ret = QSerialPort::SecondaryReceivedDataSignal;
#endif
#ifdef TIOCM_CTS
if (arg & TIOCM_CTS)
ret = QSerialPort::ClearToSendSignal;
#endif
#ifdef TIOCM_CAR
if (arg & TIOCM_CAR)
ret = QSerialPort::DataCarrierDetectSignal;
#elif defined(TIOCM_CD)
if (arg & TIOCM_CD)
ret = QSerialPort::DataCarrierDetectSignal;
#endif
#ifdef TIOCM_RNG
if (arg & TIOCM_RNG)
ret = QSerialPort::RingIndicatorSignal;
#elif defined(TIOCM_RI)
if (arg & TIOCM_RI)
ret = QSerialPort::RingIndicatorSignal;
#endif
#ifdef TIOCM_DSR
if (arg & TIOCM_DSR)
ret = QSerialPort::DataSetReadySignal;
#endif
return ret;
}
boolQSerialPortPrivate::setDataTerminalReady(bool set)
{
int status = TIOCM_DTR;
if (::ioctl(descriptor, set ? TIOCMBIS : TIOCMBIC, &status) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::setRequestToSend(bool set)
{
int status = TIOCM_RTS;
if (::ioctl(descriptor, set ? TIOCMBIS : TIOCMBIC, &status) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::flush()
{
returncompleteAsyncWrite();
}
boolQSerialPortPrivate::clear(QSerialPort::Directions directions)
{
if (::tcflush(descriptor, (directions QSerialPort::AllDirections)
? TCIOFLUSH : (directions & QSerialPort::Input) ? TCIFLUSH : TCOFLUSH) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::sendBreak(int duration)
{
if (::tcsendbreak(descriptor, duration) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::setBreakEnabled(bool set)
{
if (::ioctl(descriptor, set ? TIOCSBRK : TIOCCBRK) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::waitForReadyRead(int msecs)
{
QElapsedTimer stopWatch;
stopWatch.start();
do {
bool readyToRead = false;
bool readyToWrite = false;
if (!waitForReadOrWrite(&readyToRead, &readyToWrite, true, !writeBuffer.isEmpty(),
qt_subtract_from_timeout(msecs, stopWatch.elapsed()))) {
returnfalse;
}
if (readyToRead)
returnreadNotification();
if (readyToWrite && !completeAsyncWrite())
returnfalse;
} while (msecs -1qt_subtract_from_timeout(msecs, stopWatch.elapsed()) > 0);
returnfalse;
}
boolQSerialPortPrivate::waitForBytesWritten(int msecs)
{
if (writeBuffer.isEmpty() && pendingBytesWritten <= 0)
returnfalse;
QElapsedTimer stopWatch;
stopWatch.start();
for (;;) {
bool readyToRead = false;
bool readyToWrite = false;
if (!waitForReadOrWrite(&readyToRead, &readyToWrite, true, !writeBuffer.isEmpty(),
qt_subtract_from_timeout(msecs, stopWatch.elapsed()))) {
returnfalse;
}
if (readyToRead && !readNotification())
returnfalse;
if (readyToWrite)
returncompleteAsyncWrite();
}
returnfalse;
}
boolQSerialPortPrivate::setBaudRate()
{
if (inputBaudRate outputBaudRate)
returnsetBaudRate(inputBaudRate, QSerialPort::AllDirections);
return (setBaudRate(inputBaudRate, QSerialPort::Input)
&& setBaudRate(outputBaudRate, QSerialPort::Output));
}
boolQSerialPortPrivate::setStandardBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
#ifdef Q_OS_LINUX
// try to clear custom baud rate, using termios v2
structtermios2 tio2;
if (::ioctl(descriptor, TCGETS2, &tio2) != -1) {
if (tio2.c_cflag & BOTHER) {
tio2.c_cflag &= ~BOTHER;
tio2.c_cflag = CBAUD;
::ioctl(descriptor, TCSETS2, &tio2);
}
}
// try to clear custom baud rate, using serial_struct (old way)
structserial_struct serial;
::memset(&serial, 0, sizeof(serial));
if (::ioctl(descriptor, TIOCGSERIAL, &serial) != -1) {
if (serial.flags & ASYNC_SPD_CUST) {
serial.flags &= ~ASYNC_SPD_CUST;
serial.custom_divisor = 0;
// we don't check on errors because a driver can has not this feature
::ioctl(descriptor, TIOCSSERIAL, &serial);
}
}
#endif
termios tio;
if (!getTermios(&tio))
returnfalse;
if ((directions & QSerialPort::Input) && ::cfsetispeed(&tio, baudRate) < 0) {
setError(getSystemError());
returnfalse;
}
if ((directions & QSerialPort::Output) && ::cfsetospeed(&tio, baudRate) < 0) {
setError(getSystemError());
returnfalse;
}
returnsetTermios(&tio);
}
#if defined(Q_OS_LINUX)
boolQSerialPortPrivate::setCustomBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
if (directions != QSerialPort::AllDirections) {
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError,
QSerialPort::tr('Cannot set custom speed for one direction')));
returnfalse;
}
structtermios2 tio2;
if (::ioctl(descriptor, TCGETS2, &tio2) != -1) {
tio2.c_cflag &= ~CBAUD;
tio2.c_cflag = BOTHER;
tio2.c_ispeed = baudRate;
tio2.c_ospeed = baudRate;
if (::ioctl(descriptor, TCSETS2, &tio2) != -1
&& ::ioctl(descriptor, TCGETS2, &tio2) != -1) {
returntrue;
}
}
structserial_struct serial;
if (::ioctl(descriptor, TIOCGSERIAL, &serial) -1) {
setError(getSystemError());
returnfalse;
}
serial.flags &= ~ASYNC_SPD_MASK;
serial.flags = (ASYNC_SPD_CUST /* ASYNC_LOW_LATENCY*/);
serial.custom_divisor = serial.baud_base / baudRate;
if (serial.custom_divisor0) {
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError,
QSerialPort::tr('No suitable custom baud rate divisor')));
returnfalse;
}
if (serial.custom_divisor * baudRate != serial.baud_base) {
qWarning('Baud rate of serial port %s is set to %f instead of %d: divisor %f unsupported',
qPrintable(systemLocation),
float(serial.baud_base) / serial.custom_divisor,
baudRate, float(serial.baud_base) / baudRate);
}
if (::ioctl(descriptor, TIOCSSERIAL, &serial) -1) {
setError(getSystemError());
returnfalse;
}
returnsetStandardBaudRate(B38400, directions);
}
#elif defined(Q_OS_OSX)
boolQSerialPortPrivate::setCustomBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
if (directions != QSerialPort::AllDirections) {
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError,
QSerialPort::tr('Cannot set custom speed for one direction')));
returnfalse;
}
#if defined(MAC_OS_X_VERSION_10_4) && (MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_4)
if (::ioctl(descriptor, IOSSIOSPEED, &baudRate) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
#else
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError,
QSerialPort::tr('Custom baud rate is not supported')));
returnfalse;
#endif
}
#elif defined(Q_OS_QNX)
boolQSerialPortPrivate::setCustomBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
// On QNX, the values of the 'Bxxxx' constants are set to 'xxxx' (i.e.
// B115200 is defined to '115200'), which means that literal values can be
// passed to cfsetispeed/cfsetospeed, including custom values, provided
// that the underlying hardware supports them.
returnsetStandardBaudRate(baudRate, directions);
}
#else
boolQSerialPortPrivate::setCustomBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
Q_UNUSED(baudRate);
Q_UNUSED(directions);
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError,
QSerialPort::tr('Custom baud rate is not supported')));
returnfalse;
}
#endif
boolQSerialPortPrivate::setBaudRate(qint32 baudRate, QSerialPort::Directions directions)
{
if (baudRate <= 0) {
setError(QSerialPortErrorInfo(QSerialPort::UnsupportedOperationError, QSerialPort::tr('Invalid baud rate value')));
returnfalse;
}
const qint32 unixBaudRate = QSerialPortPrivate::settingFromBaudRate(baudRate);
return (unixBaudRate > 0)
? setStandardBaudRate(unixBaudRate, directions)
: setCustomBaudRate(baudRate, directions);
}
boolQSerialPortPrivate::setDataBits(QSerialPort::DataBits dataBits)
{
termios tio;
if (!getTermios(&tio))
returnfalse;
qt_set_databits(&tio, dataBits);
returnsetTermios(&tio);
}
boolQSerialPortPrivate::setParity(QSerialPort::Parity parity)
{
termios tio;
if (!getTermios(&tio))
returnfalse;
qt_set_parity(&tio, parity);
returnsetTermios(&tio);
}
boolQSerialPortPrivate::setStopBits(QSerialPort::StopBits stopBits)
{
termios tio;
if (!getTermios(&tio))
returnfalse;
qt_set_stopbits(&tio, stopBits);
returnsetTermios(&tio);
}
boolQSerialPortPrivate::setFlowControl(QSerialPort::FlowControl flowControl)
{
termios tio;
if (!getTermios(&tio))
returnfalse;
qt_set_flowcontrol(&tio, flowControl);
returnsetTermios(&tio);
}
boolQSerialPortPrivate::startAsyncRead()
{
setReadNotificationEnabled(true);
returntrue;
}
boolQSerialPortPrivate::readNotification()
{
Q_Q(QSerialPort);
// Always buffered, read data from the port into the read buffer
qint64 newBytes = buffer.size();
qint64 bytesToRead = QSERIALPORT_BUFFERSIZE;
if (readBufferMaxSize && bytesToRead > (readBufferMaxSize - buffer.size())) {
bytesToRead = readBufferMaxSize - buffer.size();
if (bytesToRead <= 0) {
// Buffer is full. User must read data from the buffer
// before we can read more from the port.
setReadNotificationEnabled(false);
returnfalse;
}
}
char *ptr = buffer.reserve(bytesToRead);
const qint64 readBytes = readFromPort(ptr, bytesToRead);
buffer.chop(bytesToRead - qMax(readBytes, qint64(0)));
if (readBytes <= 0) {
QSerialPortErrorInfo error = getSystemError();
if (error.errorCode != QSerialPort::ResourceError)
error.errorCode = QSerialPort::ReadError;
else
setReadNotificationEnabled(false);
setError(error);
returnfalse;
}
newBytes = buffer.size() - newBytes;
// only emit readyRead() when not recursing, and only if there is data available
constbool hasData = newBytes > 0;
if (!emittedReadyRead && hasData) {
emittedReadyRead = true;
emit q->readyRead();
emittedReadyRead = false;
}
returntrue;
}
boolQSerialPortPrivate::startAsyncWrite()
{
if (writeBuffer.isEmpty() writeSequenceStarted)
returntrue;
// Attempt to write it all in one chunk.
qint64 written = writeToPort(writeBuffer.readPointer(), writeBuffer.nextDataBlockSize());
if (written < 0) {
QSerialPortErrorInfo error = getSystemError();
if (error.errorCode != QSerialPort::ResourceError)
error.errorCode = QSerialPort::WriteError;
setError(error);
returnfalse;
}
writeBuffer.free(written);
pendingBytesWritten += written;
writeSequenceStarted = true;
if (!isWriteNotificationEnabled())
setWriteNotificationEnabled(true);
returntrue;
}
boolQSerialPortPrivate::completeAsyncWrite()
{
Q_Q(QSerialPort);
if (pendingBytesWritten > 0) {
if (!emittedBytesWritten) {
emittedBytesWritten = true;
emit q->bytesWritten(pendingBytesWritten);
pendingBytesWritten = 0;
emittedBytesWritten = false;
}
}
writeSequenceStarted = false;
if (writeBuffer.isEmpty()) {
setWriteNotificationEnabled(false);
returntrue;
}
returnstartAsyncWrite();
}
inlineboolQSerialPortPrivate::initialize(QIODevice::OpenMode mode)
{
#ifdef TIOCEXCL
if (::ioctl(descriptor, TIOCEXCL) -1)
setError(getSystemError());
#endif
termios tio;
if (!getTermios(&tio))
returnfalse;
restoredTermios = tio;
qt_set_common_props(&tio, mode);
qt_set_databits(&tio, dataBits);
qt_set_parity(&tio, parity);
qt_set_stopbits(&tio, stopBits);
qt_set_flowcontrol(&tio, flowControl);
if (!setTermios(&tio))
returnfalse;
if (!setBaudRate())
returnfalse;
if (mode & QIODevice::ReadOnly)
setReadNotificationEnabled(true);
returntrue;
}
qint64 QSerialPortPrivate::writeData(constchar *data, qint64 maxSize)
{
writeBuffer.append(data, maxSize);
if (!writeBuffer.isEmpty() && !isWriteNotificationEnabled())
setWriteNotificationEnabled(true);
return maxSize;
}
boolQSerialPortPrivate::setTermios(const termios *tio)
{
if (::tcsetattr(descriptor, TCSANOW, tio) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
boolQSerialPortPrivate::getTermios(termios *tio)
{
::memset(tio, 0, sizeof(termios));
if (::tcgetattr(descriptor, tio) -1) {
setError(getSystemError());
returnfalse;
}
returntrue;
}
QSerialPortErrorInfo QSerialPortPrivate::getSystemError(int systemErrorCode) const
{
if (systemErrorCode -1)
systemErrorCode = errno;
QSerialPortErrorInfo error;
error.errorString = qt_error_string(systemErrorCode);
switch (systemErrorCode) {
case ENODEV:
error.errorCode = QSerialPort::DeviceNotFoundError;
break;
#ifdef ENOENT
case ENOENT:
error.errorCode = QSerialPort::DeviceNotFoundError;
break;
#endif
case EACCES:
error.errorCode = QSerialPort::PermissionError;
break;
case EBUSY:
error.errorCode = QSerialPort::PermissionError;
break;
case EAGAIN:
error.errorCode = QSerialPort::ResourceError;
break;
case EIO:
error.errorCode = QSerialPort::ResourceError;
break;
case EBADF:
error.errorCode = QSerialPort::ResourceError;
break;
#ifdef Q_OS_OSX
case ENXIO:
error.errorCode = QSerialPort::ResourceError;
break;
#endif
#ifdef EINVAL
case EINVAL:
error.errorCode = QSerialPort::UnsupportedOperationError;
break;
#endif
#ifdef ENOIOCTLCMD
case ENOIOCTLCMD:
error.errorCode = QSerialPort::UnsupportedOperationError;
break;
#endif
#ifdef ENOTTY
case ENOTTY:
error.errorCode = QSerialPort::UnsupportedOperationError;
break;
#endif
#ifdef EPERM
case EPERM:
error.errorCode = QSerialPort::PermissionError;
break;
#endif
default:
error.errorCode = QSerialPort::UnknownError;
break;
}
return error;
}
boolQSerialPortPrivate::isReadNotificationEnabled() const
{
return readNotifier && readNotifier->isEnabled();
}
voidQSerialPortPrivate::setReadNotificationEnabled(bool enable)
{
Q_Q(QSerialPort);
if (readNotifier) {
readNotifier->setEnabled(enable);
} elseif (enable) {
readNotifier = newReadNotifier(this, q);
readNotifier->setEnabled(true);
}
}
boolQSerialPortPrivate::isWriteNotificationEnabled() const
{
return writeNotifier && writeNotifier->isEnabled();
}
voidQSerialPortPrivate::setWriteNotificationEnabled(bool enable)
{
Q_Q(QSerialPort);
if (writeNotifier) {
writeNotifier->setEnabled(enable);
} elseif (enable) {
writeNotifier = newWriteNotifier(this, q);
writeNotifier->setEnabled(true);
}
}
boolQSerialPortPrivate::waitForReadOrWrite(bool *selectForRead, bool *selectForWrite,
bool checkRead, bool checkWrite,
int msecs)
{
Q_ASSERT(selectForRead);
Q_ASSERT(selectForWrite);
pollfd pfd = qt_make_pollfd(descriptor, 0);
if (checkRead)
pfd.events = POLLIN;
if (checkWrite)
pfd.events = POLLOUT;
constint ret = qt_poll_msecs(&pfd, 1, msecs);
if (ret < 0) {
setError(getSystemError());
returnfalse;
}
if (ret 0) {
setError(QSerialPortErrorInfo(QSerialPort::TimeoutError));
returnfalse;
}
if (pfd.revents & POLLNVAL) {
setError(getSystemError(EBADF));
returnfalse;
}
*selectForWrite = ((pfd.revents & POLLOUT) != 0);
*selectForRead = ((pfd.revents & POLLIN) != 0);
returntrue;
}
qint64 QSerialPortPrivate::readFromPort(char *data, qint64 maxSize)
{
returnqt_safe_read(descriptor, data, maxSize);
}
qint64 QSerialPortPrivate::writeToPort(constchar *data, qint64 maxSize)
{
qint64 bytesWritten = 0;
#if defined(CMSPAR)
bytesWritten = qt_safe_write(descriptor, data, maxSize);
#else
if (parity != QSerialPort::MarkParity
&& parity != QSerialPort::SpaceParity) {
bytesWritten = qt_safe_write(descriptor, data, maxSize);
} else {// Perform parity emulation.
bytesWritten = writePerChar(data, maxSize);
}
#endif
return bytesWritten;
}
#ifndef CMSPAR
staticinlineboolevenParity(quint8 c)
{
c ^= c >> 4; //(c7 ^ c3)(c6 ^ c2)(c5 ^ c1)(c4 ^ c0)
c ^= c >> 2; //[(c7 ^ c3)(c5 ^ c1)][(c6 ^ c2)(c4 ^ c0)]
c ^= c >> 1;
return c & 1; //(c7 ^ c3)(c5 ^ c1)(c6 ^ c2)(c4 ^ c0)
}
qint64 QSerialPortPrivate::writePerChar(constchar *data, qint64 maxSize)
{
termios tio;
if (!getTermios(&tio))
return -1;
qint64 ret = 0;
quint8 const charMask = (0xFF >> (8 - dataBits));
while (ret < maxSize) {
bool par = evenParity(*data & charMask);
// False if need EVEN, true if need ODD.
par ^= parity QSerialPort::MarkParity;
if (par ^ (tio.c_cflag & PARODD)) { // Need switch parity mode?
tio.c_cflag ^= PARODD;
flush(); //force sending already buffered data, because setTermios(&tio); cleares buffers
//todo: add receiving buffered data!!!
if (!setTermios(&tio))
break;
}
int r = qt_safe_write(descriptor, data, 1);
if (r < 0)
return -1;
if (r > 0) {
data += r;
ret += r;
}
}
return ret;
}
#endif//CMSPAR
typedef QMap<qint32, qint32> BaudRateMap;
// The OS specific defines can be found in termios.h
staticconst BaudRateMap createStandardBaudRateMap()
{
BaudRateMap baudRateMap;
#ifdef B50
baudRateMap.insert(50, B50);
#endif
#ifdef B75
baudRateMap.insert(75, B75);
#endif
#ifdef B110
baudRateMap.insert(110, B110);
#endif
#ifdef B134
baudRateMap.insert(134, B134);
#endif
#ifdef B150
baudRateMap.insert(150, B150);
#endif
#ifdef B200
baudRateMap.insert(200, B200);
#endif
#ifdef B300
baudRateMap.insert(300, B300);
#endif
#ifdef B600
baudRateMap.insert(600, B600);
#endif
#ifdef B1200
baudRateMap.insert(1200, B1200);
#endif
#ifdef B1800
baudRateMap.insert(1800, B1800);
#endif
#ifdef B2400
baudRateMap.insert(2400, B2400);
#endif
#ifdef B4800
baudRateMap.insert(4800, B4800);
#endif
#ifdef B7200
baudRateMap.insert(7200, B7200);
#endif
#ifdef B9600
baudRateMap.insert(9600, B9600);
#endif
#ifdef B14400
baudRateMap.insert(14400, B14400);
#endif
#ifdef B19200
baudRateMap.insert(19200, B19200);
#endif
#ifdef B28800
baudRateMap.insert(28800, B28800);
#endif
#ifdef B38400
baudRateMap.insert(38400, B38400);
#endif
#ifdef B57600
baudRateMap.insert(57600, B57600);
#endif
#ifdef B76800
baudRateMap.insert(76800, B76800);
#endif
#ifdef B115200
baudRateMap.insert(115200, B115200);
#endif
#ifdef B230400
baudRateMap.insert(230400, B230400);
#endif
#ifdef B460800
baudRateMap.insert(460800, B460800);
#endif
#ifdef B500000
baudRateMap.insert(500000, B500000);
#endif
#ifdef B576000
baudRateMap.insert(576000, B576000);
#endif
#ifdef B921600
baudRateMap.insert(921600, B921600);
#endif
#ifdef B1000000
baudRateMap.insert(1000000, B1000000);
#endif
#ifdef B1152000
baudRateMap.insert(1152000, B1152000);
#endif
#ifdef B1500000
baudRateMap.insert(1500000, B1500000);
#endif
#ifdef B2000000
baudRateMap.insert(2000000, B2000000);
#endif
#ifdef B2500000
baudRateMap.insert(2500000, B2500000);
#endif
#ifdef B3000000
baudRateMap.insert(3000000, B3000000);
#endif
#ifdef B3500000
baudRateMap.insert(3500000, B3500000);
#endif
#ifdef B4000000
baudRateMap.insert(4000000, B4000000);
#endif
return baudRateMap;
}
staticconst BaudRateMap& standardBaudRateMap()
{
staticconst BaudRateMap baudRateMap = createStandardBaudRateMap();
return baudRateMap;
}
qint32 QSerialPortPrivate::settingFromBaudRate(qint32 baudRate)
{
returnstandardBaudRateMap().value(baudRate);
}
QList<qint32> QSerialPortPrivate::standardBaudRates()
{
returnstandardBaudRateMap().keys();
}
QSerialPort::HandleQSerialPort::handle() const
{
Q_D(const QSerialPort);
return d->descriptor;
}
QT_END_NAMESPACE
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Hi. I faced a strange problem using serial port.
I can't write on serial port by a thread loop!!
however I can write on it by thread constructor!
I can read from serial port in thread but I can't write on it. I don't know where is the problem but by my personal experience in using QSerialPort I think Serial port in Qt have some issues with thread! because it's not my firs problem with QSerialPort and QThread together. maybe I'm wrong but I wrote this code before with c# and this sort of things are not issue there!
thanks in advices.

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