Hello,
I have a serial hardware device that is sending a certain (hardware-controlled) numeric value in the range [0 .. 255] over and over again.
I am sure the device is sending the correct value, but when I am trying to read it through an instance of QextSerialPort, I am getting wrong values.
And even when changing that (hardware-controlled) value, I am reading the same old wrong value

Here is the code used (a modified version of the example shipped with QextSerialPort):

Qt Code: 
  1. /* qesptest.h
  2. **************************************/
  3.  
  4. #ifndef _QESPTEST_H_
  5. #define _QESPTEST_H_
  6.  
  7. #include <QWidget>
  8.  
  9.  
  10. class QTextEdit;
  11. class QextSerialPort;
  12.  
  13. class QespTest :  public QWidget
  14. {
  15.   Q_OBJECT
  16. public:
  17.   QespTest(QWidget *parent=0);
  18.  
  19.   virtual ~QespTest();
  20.  
  21. private:
  22.   QTextEdit *received_msg;
  23.   QextSerialPort *port;
  24.  
  25. private slots:
  26.   void receiveByte();
  27. };
  28.  
  29. #endif
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charToBinaryStdString() is created so that I can display the read char as 1s and 0s...
Qt Code: 
  1. /* qesptest.cpp
  2. **************************************/
  3. #include "qesptest.h"
  4. #include <qextserialport.h>
  5. #include <QLayout>
  6. #include <QTextEdit>
  7. #include <QPushButton>
  8. #include <string>
  9.  
  10. QespTest::QespTest(QWidget* parent)
  11. 	: QWidget(parent)
  12.  
  13. {
  14. 	//port settings
  15. 	port = new QextSerialPort("COM1");
  16. 	port->setBaudRate(BAUD9600);
  17. 	port->setFlowControl(FLOW_XONXOFF);
  18. 	port->setParity(PAR_NONE);
  19. 	port->setDataBits(DATA_8);
  20. 	port->setStopBits(STOP_1);
  21. 	port->open(QIODevice::ReadOnly);
  22.  
  23. 	QPushButton *receiveButton = new QPushButton("Receive");
  24. 	connect(receiveButton, SIGNAL(clicked()), SLOT(receiveByte()));
  25.  
  26. 	received_msg = new QTextEdit();
  27.  
  28. 	QVBoxLayout *myVBox = new QVBoxLayout;
  29. 	myVBox->addWidget(receiveButton);
  30. 	myVBox->addWidget(received_msg);
  31. 	setLayout(myVBox);
  32. }
  33.  
  34. QespTest::~QespTest()
  35. {
  36. 	port->close();
  37. 	delete port;
  38. 	port = NULL;
  39. }
  40.  
  41. std::string charToBinaryStdString(char ch)
  42. {
  43. 	std::string result;
  44. 	int i = 8;
  45.  
  46. 	while (i >0)
  47. 	{
  48. 		--i;
  49. 		result += (ch&(1 << i) ? '1' : '0');
  50. 	}
  51.  
  52. 	return result;
  53. }
  54.  
  55. void QespTest::receiveByte()
  56. {
  57. 	port->open(QIODevice::ReadOnly);
  58.  
  59. 	char ch;
  60. 	if(port->bytesAvailable() > 0)
  61. 	{
  62. 		port->read(&ch,1);
  63. 		received_msg->append(QString::fromStdString(charToBinaryStdString(ch)));
  64. 	}
  65. }
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main() just includes an instance of QespTest and QApplication...

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What's wrong?