Hello
I can’t get the functions waitForReadyRead() and bytesAvailable() to work as I expect them to.
I’m using Qt 4.7.4, Win 7, MinGW compiler.
QtSerialPort downloaded 11 Feb 2013.
The code in short is:
openSerialPort();
if(serial->isOpen())
{
serial->flush();
RS232Cmd[0] = 0x1B; // 2 bytes, Esc A
RS232Cmd[1] = 'A';
serial->write(RS232Cmd,2);
serial->waitForBytesWritten(100);
bTest = serial->waitForReadyRead(5000);
qDebug("w %d", bTest);
temp_value = serial->bytesAvailable();
temp_value2 = serial->read(RS232Buffer, 8);
qDebug("a %d", temp_value);
qDebug("r %d", temp_value2);
closeSerialPort();
}
The output I get is this:
w 0
a 0
r 0
First of all, with the 5000 parameter to waitForReadyRead(); I expect the program to wait 5 seconds before displaying the debug output if no data comes in, but there is no wait time that I can notice.
Second, I can see on the oscilloscope that the two bytes (‘Esc’ + ‘A’) are sent and that a 8 byte reply is received within 2ms.
Third, with a terminal program I can verify that the 8 byte reply is correctly received on the PC.
Any ideas on what’s going wrong?
Or have I misunderstood the functionality of these functions?
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