[Qt-interest] Qextserialport time out question

[Phil]

Thank you for reading this.

This is a long standing problem that I have never been able to solve. If I 
initialise the serial port as follows then it takes one second to read five 
bytes. If I don't set the time out parameter or set it to anything less than 
one second then the read fails.

However, if I step through the code with the debugger then the device is 
read correctly so it's a timing issue somewhere.

Can anyone suggest a likely cure?

port = new QextSerialPort("/dev/ttyUSB0");
port->setBaudRate(BAUD4800);
port->setFlowControl(FLOW_OFF);
port->setParity(PAR_NONE);
port->setDataBits(DATA_8);
port->setStopBits(STOP_2);
port->setTimeout(1,0); //1 second

do
{
  bytes = port->bytesAvailable();
  error = port->lastError();

    if(error == E_PORT_TIMEOUT)
      return -1;

} while(bytes < 5);

port->read(buffer, 5);

Could the USB to serial converter be the cause of the timing problem? It 
woks perfectly except in this application.

-- 
Regards,
Phil