Serial port communication in Qt - qt

Question

I am new to Qt and need to prepare a project to send hex commands from rs232.
QString line contains 64bit binary data which i have to convert into hexadecimal and send it through rs232 .
QString a=ui->comboBox->currentText();
QString s1;
s1="./calc "+a;
QProcess p1;
p1.start(s1);
p1.waitForFinished(-1);
QString line ;
//read
QFile file("TeleOutput.txt");
if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
return;
QTextStream in (&file);
line = in.readAll();
ui->plainTextEdit->setPlainText(line);
So, how to convert 64 bit binary data in QString line to hexadecimal value and transfer it through rs232?

Answer 1

First of all - you should really use QtSerialPort
Second of all - QString is a class, which works with actual string. QByteArray works with raw data. When you write QString line = in.readAll(); it implicitly calls QString(const QByteArray &ba), which uses QString::fromAscii.
Last of all, if you want to process 64bit integers, you should do something like this:
quint64 d;
QDataStream stream(&file);
while (!stream.atEnd())
{
stream >> d;
process(d);
}
Update
Quote:
My problem is that in plainTextEdit
"1111110101000101010101010101010101010101010101010101010......." 64
bit data is populated , i need to convert this data into hex and send it through rs232
Solution:
QString binData = plainTextEdit.toPlainText();
QByteArray result;
while (binData.size() >= 64)
{
quint64 d;
QString dataPiece = binData.left(64);
binData.remove(0, 64);
d = dataPiece.toULongLong(0, 2);
result += QByteArray::number(d);
}
_com->write(result);
_com->flush();
Where _com is a pointer to QtSerialPort, with all parameters set and opened without errors.