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  1. #1
    Join Date
    Feb 2014
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    Qt products
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    Platforms
    Unix/X11

    Post Problem in reading data from the serial port to byte array

    Hello all,
    I am new to Qt and please excuse me for my English, am writing code to controll the finger print reader(R305 module) with serial communication. I am writing the data to device successfully but i am unable to get the data to a bytearray and failed to verify received data with my data.

    The below is the code for reading and writing data...

    Qt Code:
    1. void MainWindow::on_pushButton_clicked()
    2. {
    3.  
    4. const char enable[12]={0xEF,0X01,0XFF,0XFF,0XFF,0XFF,0X01,0X00,0X03,0X01,0X00,0X05};
    5.  
    6. QByteArray data = QByteArray::fromRawData(enable, sizeof(enable));
    7.  
    8. textEdit->setText(data);
    9. qDebug()<<"\n enabletext123:"<<textEdit->toPlainText();
    10.  
    11. writeData(data);
    12.  
    13. }
    14.  
    15. void MainWindow::on_pushIdentity_clicked()
    16. {
    17. const char identify[17]={0xef,0x01,0xff,0xff,0xff,0xff,0x01,0x00,0x08,0x1b,0x01,0x00,0x00,0x01,0x01,0x00,0x27};
    18.  
    19. QByteArray data1 = QByteArray::fromRawData(identify, sizeof(identify));
    20. // port->write(data);
    21.  
    22. textEdit->setText(data1);
    23. qDebug()<<"\n identytext1234:"<<textEdit->toPlainText();
    24.  
    25. writeData(data1);
    26. }
    27.  
    28. void MainWindow::writeData(const QByteArray &data)
    29. {
    30.  
    31. qDebug()<< port->write(data);
    32. qDebug()<<"write data:"<<data;
    33. for(int i=0;i<=5000;i++);
    34. }
    35.  
    36.  
    37. void MainWindow::readData()
    38. {
    39. port->flush();
    40. QByteArray response=port->readAll();
    41. int count=response.size();
    42. qDebug()<<"\n no. of bytes read"<<response.count();
    43.  
    44. textEdit->append(response)
    45.  
    46. qDebug()<<"read data:"<<response;
    47. }
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    My debug output is showing like this...and the textEdit not displaying this garbage data...The problem is, i am not getting any idea that what is happing..but the reader is blinking when i press the enable button..

    Starting /home/hari/Videos/qt_projects2/Fingerprint-build-Desktop-Debug/Fingerprint...
    Number of serial ports: 1
    Name: "ttyS0"
    true ok
    Baud rate: 9600
    Data bits: 8
    Stop bits: 1
    Parity: 0
    Flow control: 0
    Read buffer size: 0

    enabletext123: "�����"
    12
    write data: "�����
    no. of bytes read 8
    read data: "�����
    no. of bytes read 4
    read data: "
    identytext1234: "�����"
    17
    write data: "�����
    no. of bytes read 8
    read data: "�����
    no. of bytes read 8
    read data: " U&
    /home/hari/Videos/qt_projects2/Fingerprint-build-Desktop-Debug/Fingerprint exited with code 0


    Please suggest some modifications to get the data understandable for me...ASAP...
    Thanks in advance..
    Last edited by anda_skoa; 15th March 2014 at 15:37. Reason: missing [code] tags

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