This is actually serial port communication via the USB port. I am talking to a PIC based microcontroller. I read all the serial ports, identify the one to which the microcontroller is attached; Then I send 0xE0 repeatedly and read all the data sent over the serial port with a readAll().

When I send the 0xE0 over the serial port using "realterm serial port communication program", the microcontroller sends data for nearly a second, the status of all 15 I/O ports.

When I use the qserialport I hardly get 10 bytes and that too, not every time, also it does not take 1 second to read unlike in the realterm application!
@#include <QCoreApplication>
#include <QDebug>
#include <QSerialPort>
#include <QSerialPortInfo>
#include <QIODevice>

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
QString portID;

qDebug() << "Number of serial ports:" << QSerialPortInfo::availablePorts().count();

foreach (const QSerialPortInfo &serialPortInfo, QSerialPortInfo::availablePorts()) {

    qDebug() << "\nPort:" << serialPortInfo.portName();
    if (serialPortInfo.description() == "Communications Port") portID = serialPortInfo.portName();

}
printf ("Opening Port %s\n",qPrintable(portID));
if (portID.size() > 1)
{
    //could do  reinterpret_cast and have const unsigned char
    unsigned char temp_char = 0xE0;
    QSerialPort embed;
    embed.setPortName(portID);
    embed.setBaudRate(QSerialPort::Baud115200);
    embed.setDataBits(QSerialPort::Data8);
    embed.setParity(QSerialPort::NoParity);
    embed.setStopBits(QSerialPort::OneStop);
    embed.open(QIODevice::ReadWrite);
    embed.write(reinterpret_cast<const char*>(&temp_char),1);

    int numRead = 0,numReadTotal = 0;
    QByteArray buffer;

    for (int i=1; i<=20;i++) {
        QCoreApplication::processEvents( QEventLoop::AllEvents );
        buffer = embed.readAll();
        numRead  = buffer.size();
        printf ("%d Reading Port Data count %d\n",i, numRead);
        for (int j = 0; j < numRead; j++)
            printf ("Data %x, count %d\n",buffer.at(j),j+1);
        // Do whatever with the array

        numReadTotal += numRead;
        if (numRead == 0 && (numReadTotal > 100))
            break;
        embed.write(reinterpret_cast<const char*>(&temp_char));
    }
    embed.close();
}
else printf("Port Not Found!\n");

return 0;

}@
Any suggestions on where to look for a bug?