CSerial - A C++ Class for Serial Communications

Preface

Introduction

CSerial class member functions

• CSerial::CSerial() -
• CSerial::CSerial() - Basic c'tor that takes no arguments.
• CSerial::Open(int nPort = 2, int nBaud = 9600 ) - This member function is used to open the serial port. It takes two interger arguments. The first argument contains the port number where the valid entries are 1 through 4. The second argument is the baud rate. Valid values for this argument are 1200, 2400, 4800, 9600, 19200, 38400 and 76800. This function returns TRUE if successful. Otherwise, it returns a value of FALSE.
• CSerial::Close() - While the d'tor will automatically close the serial port for you, this function has been added just in case there is a reason that you need to explicit close the port.
• CSerial::SendData(const char *, int) - This function writes data from a buffer to the serial port. The first argument it takes is a const char* to a buffer that contains the data being sent. The second argument is the number of bytes being sent. This function will return the actual number of bytes that are succesfully transmitted.
• CSerial::ReadDataWaiting(void) - This function simply returns the number of bytes that waiting in the communication port's buffer. It basically allows you to "peek" at the buffer without actually retrieving the data.
• CSerial::ReadData(void*, int) - This function reads data from the port's incoming buffer. The first argument that it takes is a void* to a buffer into which the data will be placed. The second argument is an integer value that gives the size of the buffer. The return value of this function contains the number of bytes that were successfully read into the provided data buffer.

Example Usage

Opening the serial port

CSerial serial;
if (serial.Open(2, 9600))
 AfxMessageBox("Port opened successfully");
else
 AfxMessageBox("Failed to open port!");

Sending Data

CSerial serial;
if (serial.Open(2, 9600))
{
 static char* szMessage[] = "This is test data";
 int nBytesSent = serial.SendData(szMessage, strlen(szMessage));
 ASSERT(nBytesSent == strlen(szMessage));
}
else
 AfxMessageBox("Failed to open port!");

Reading Data

CSerial serial;
if (serial.Open(2, 9600))
{
 char* lpBuffer = new char[500];
 int nBytesRead = serial.ReadData(lpBuffer, 500);
 delete []lpBuffer;
}
else
 AfxMessageBox("Failed to open port!");

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