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    • M

      Unsolved Serial data received
      General and Desktop • qt c++ serialport data buffer • • manel.sam

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      M

      @manel-sam said in Serial data received:

      So the append I should do it where§?

      Create a member variable in your imu class.

      // _packetData member variable of imu _packetData.append(serialPort->readAll()); if(_packetData.size()>=PACKET_LENGTH) { // packet complete qInfo() << QStringLiteral("data size is : ") << _packetData.size() << " octets"; qDebug() << "Serial received " << _packetData.toHex(); // go ahead with this packet QDataStream stream(_packetData); // Read The BigIndian value stream.setByteOrder(QDataStream::BigEndian); qint16 headerSignature; stream >> headerSignature; }

      You may also check the data received don't exceed PACKET_LENGTH, cause it means you have already received data from the next packet. (it may be irrelevant in your case, I don't kown)

    • A

      Unsolved LNK2019 y LNK1120 using sapera sdk for camera genie nano y openCV
      3rd Party Software • sapera opencv lnk2019 lnk1120 buffer • • ADR_PT

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      SGaist

      Hi and welcome to devnet,

      Are you sure you are linking all the required libraries ?
      Are they all from compatible compilers ?

    • R

      Unsolved QAuidoInput buffer size problem
      General and Desktop • qaudioinput buffer qt5.9 • • returnx

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      SGaist

      Hi,

      See the documentation of bufferSize, you may not get what you requested because setting e.g. a too small buffer size might trigger overflow problem.

    • S

      Unsolved Audio Input buffer - Trying to access Audio Input on a sample by sample basis
      General and Desktop • qaudioinput audio buffer • • SamSpreadborough

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      SGaist

      Hi and welcome to devnet,

      QAudioInput returns a pointer to a QIODevice that will provide the audio data. Connect the readyRead signal from that QIODevice object to a slot of your class, there you can read the audio data received and make what you want with it.

      Hope it helps

    • AllanE

      Unsolved Modify QML MediaPlayer buffer size
      QML and Qt Quick • qml media player buffer • • AllanE

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      J

      @AllanE

      Any luck with this? We're using a MediaPlayer component in our application and I'd like to programmatically adjust the buffer to produce a smoother live-media playback experience?

      Jordan

    • TriNityGER

      Unsolved QSurfaceFormat buffer sizes
      Game Development • qsurfaceformat buffer • • TriNityGER

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      No one has replied

    • M

      Unsolved QMediaPlayer eats the initial part of audio files
      Mobile and Embedded • qmultimedia qmediaplayer audio buffer delay • • Mark81

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      SGaist

      Hi,

      Usually, to play sound effect, the QSoundEffect class is used. Wouldn't that fill your need ?

    • F

      Unsolved Buffer/delay video frames from QCamera
      General and Desktop • qcamera qvideoframe buffer delay • • felet

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      SGaist

      The Android and Desktop backend don't necessarily work the same way since they rely on the platform multimedia APIs and they may use different types of data to store the video data.

      One thing that I find strange in your code is that you are overwriting input with the content of buffer rather than returning it.

    • R

      Solved Key buffer issue with my QWizard program
      General and Desktop • qwizard qwizardpage keys buffer • • roseicollis

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      kshegunov

      @roseicollis

      O.o is there any other type of question? Maybe I did it wrong... :S

      There's a "general topic" and a "question topic".

      I don't get why can't you upload a pic like before and you have to use that which I suppose is another webpage...

      Look here.

    • F

      Serial Data "reading" disorder
      General and Desktop • arduino series buffer • • ftsm

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      mrjj

      @ftsm
      Congratulations with the baby ;)

    • ?

      Solved When does QSerialPort send data from the buffer to the serial interface?
      General and Desktop • qserialport buffer serial interfac • • A Former User

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      SGaist

      I didn't saw that there was no tooltip for them… At least there is for the flag and quote :)

      Thanks :)

    • M

      QSerialPort Buffer Problems
      General and Desktop • serial port buffer qserialport overflow • • metty

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      M

      I am sorry about my last post. I made a stupid error. I updatet to QT5.5, but I haven't reconfigurated the project, so I was still using QT5.4.
      Now I tried also the Chipi-X10 USB-RS converters. I have to say, they work a lot better. I have now for all three ports, this converter. With the others, a lot of times I had to unplug and replug the connectors to get dem work. So there is something strange. The Chipi worked really good until now, thank you jeroen3, this will save a lot of time.
      After building the programm with QT5.5, the programm also work a lot better. I saw that the qcustemplot keeps plotting while I drag and drop the window. I have sometimes errors but now only sporadic. For example when I resize the window very fast, I can provoke it. But in general the errorrate is about one or two percent, and with that I can live.

      PS: We here do not play in telepathists and predictors. If you want to get help, you should provide the minimal and simple example....

      My problem was, that with the minimal simple example all seems to working. This communication problem I had only, wenn all the data was coming and when I was plotting someting in the same time. And I checked my code a lot of times. The problem is, my knowhow about QT and generell about programming with PCs is not very big. So I think there is something I do not know. So when I check my code a hundet times more, I will not find an error.

      I made also an easy experiment to isolate the error:
      My I slowed up the replot, so that I plot only every tenth time, but ten points at the same time. Like this I can see, that this error, comes only when the window is plotting. The error comes more, the more points he has to plot on the screen. So if I make fullscreen, and I set up the scale so that I have the maximum of points in the axis, the error comes every time again.
      So QT has an influence to this problem. I think there is an overflow in some buffer, beause the program is to slow to read it or that he overwrites any part for some other reasons. But anyway.. For me I will pay attention now to not overcharge my comuter :)
      Thank you for all help!