读写十六进制trame qt串行端口

Question

How can I write and read hex data when I open serial port?

if (serial->isOpen()) {
    qDebug() << "seccus: " ;
    static const char buff[] = {0xA1, 0xFF, 0xFF, 0x00,97};
    serial->write(buff,sizeof(buff));
}
if (serial->bytesAvailable()) {   // If there are bytes available
    QByteArray f_data; // data container
    f_data.clear();

    if (serial->open(QIODevice::ReadWrite)) { // Try to open the port
        while(serial->bytesAvailable()) { // Reading loop
            f_data.append(serial->readAll());
       }

       serial->flush();
    }
    qDebug()<< "the result" << f_data; // Check the result
}

if(!serial->isOpen())
    qDebug() << "carte disconnect"<<serial->errorString();

Answer 1

To debug your issue, I would start with simplifying what you're trying to do. Try writing some test code to start, to make sure things work as you expect:

1. Test serial is open - should not be
2. Open serial
3. Test serial is open - should be
4. Test if bytes are available - should not be
5. write data to serial. Flush.
6. Test if bytes are available - should be
7. Read and print to screen (ie test your reading it correctly)
8. Close the serial port - test its not open

Perhaps if one of these steps doesn't work as you expect, you can at least focus on why that particular part is not working.

Good luck.