[solved] QSerialPort error - "is a directory"
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This code gives an error of "Is a directory" when open() is called. I assume it's permissions or something but I can't find a single instance ANYWHERE online of someone else getting this error?
[code]
#include <QCoreApplication>
#include <QDebug>
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo>int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
QSerialPortInfo serialPortInfo("/dev/ttyUSB0");
QSerialPort serialPort(serialPortInfo);QByteArray byteArrayRequest; byteArrayRequest.resize(2); byteArrayRequest[0] = 0x01; byteArrayRequest[1] = 0x01; if (serialPort.open(QIODevice::ReadWrite)) { serialPort.setBaudRate(QSerialPort::Baud38400); qDebug() << "Writing\n"; serialPort.write(byteArrayRequest); serialPort.close(); } else { qDebug() << serialPort.errorString(); qDebug() << "Problem opening port\n"; } return a.exec();
}
[/code]
Can anyone please advise?
Thanks
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Hi,
What does ls -la /dev/ttyUSB0 return ?
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[quote author="SGaist" date="1393630095"]What does ls -la /dev/ttyUSB0 return ?[/quote]
If the device IS NOT plugged in:
ls: cannot access /dev/ttyUSB0: No such file or directoryIf the device IS plugged in:
crw-rw---- 1 root uucp 188, 0 Mar 1 21:27 /dev/ttyUSB0 -
Are you member of the uucp group ?
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[quote author="SGaist" date="1393714479"]Are you member of the uucp group ?[/quote]
I have run my code as root.
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OK, so I figured I must be referencing the port incorrectly.
This post was useful -> http://qt-project.org/forums/viewthread/28942
I changed the hardcoded reference to /dev/ttyUSB0 in my code and loaded it in the same way as the posts do and it worked fine!
Thanks :)
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You're welcome !
Since you have your serial port talking now, please update your thread title prepending [solved] so other forum users may know a solution has been found :)