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We strongly advise against using it in new code.įraming error detected by the hardware while reading data. Parity error detected by the hardware while reading data. This value was introduced in QtSerialPort 5.2. This error occurs when an operation is executed that can only be successfully performed if the device is open. When an error occurs in the serial port, the errorOccurred() signal will be triggered, and we can respond to this signal and call the error() interface to obtain specific error information.Īn error occurred while attempting to open an non-existing device.Īn error occurred while attempting to open an already opened device by another process or a user not having enough permission and credentials to open.Īn error occurred while attempting to open an already opened device in this object. When reading, you can call the waitForReadyRead() interface to wait for new data to be read: You can read and write separately by calling the read() or write() function, or you can call readLine() and readAll() to read. Since the QSerialPort class inherits from the QIODevice class, the interface functions for IO operations are suitable for the serial port class. Once the serial port is set up and opened, data can be read and written. QDebug() << " COM1 SeriPort open failed!" QDebug() << "COM1 SeriPort open sucess!" If (m_serialPort->open(QSerialPort::ReadWrite)) M_serialPort->setFlowControl(QSerialPort::NoFlowControl) M_serialPort->setParity(QSerialPort::NoParity) M_serialPort->setDataBits(QSerialPort::Data8) M_serialPort->setStopBits(QSerialPort::OneStop) M_serialPort->setBaudRate(QSerialPort::Baud115200) QSerialPort *m_serialPort if (m_serialPort->isOpen()) Therefore, it is best to judge whether it is opened before opening. It should be noted that the serial port can only be opened once, that is, the serial port that has been opened cannot be opened. Similar controls can also have read-only (r/o), write-only (w/o). QSerialPort::ReadWrite shows that the serial port is readable and writable. These configurations can also be set through the QSerialPortInfo class. The operation of opening the serial port requires setting the serial port name, setting the baud rate and some other configurations. Provides information about existing serial ports Provides functions to access serial ports When using, you need to add module support and add header file support in the file calling the relevant interface: Including configuration, I/O operation, obtaining and setting RS-232 control pin signals, etc. Qt Serial Port provides basic serial port operation interface functions. There is no serial port module support in Qt4, but since Qt5.1, the official serialport module has been added, so that we can easily use this module to implement cross-platform serial port operations. Switch(CMUCOM.peek(&data,1))Ĭase-1:throwCMUCOM.This article will summarize Qt's serial programming. Qint64len=CMUCOM.write((constchar*)buffer,(qint64)size) Size_tCMUcom4::write(constuint8_t*buffer,size_tsize) ReturnCMUCOM.putChar((char)c)?1:throwCMUCOM.errorString() Switch(CMUCOM.read(&c,1))Ĭase-1:throwCMUCOM.errorString() Ĭase0:return-1 ĭefault:break Q.exec() Īnd then the child preforms I/O with this code. QFuturefuture=QtConcurrent::run(&CMUCAM,&CMUcam4::begin) QFutureWatcherwatcher Ĭonnect(&watcher,SIGNAL(finished()),&q,SLOT(quit()))
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sleep.msleep(100) ĬtDtr(true) ĬtRts(true) ĬtDtr(false) ĬtRts(false) Return ĬtBaudRate(BAUD19200) ĬtDataBits(DATA_8) ĬtFlowControl(FLOW_OFF) ĬtParity(PAR_NONE) ĬtStopBits(STOP_1) ĬtTimeout(500) QMessageBox::critical(this,tr("Error"),CMUCOM.errorString()) I spawn the child thread in this section.ĬtPortName(item) ĬtQueryMode(QextSerialPort::Polling) So, I'm having some weird problems with the qextserialport library/ It seems when I call the read function with a child thread even after verifying that there are bytes in a buffer that the child thread never returns from read.