使用C ++从Arduino读取串行数据

Question

So that's what I want to do. I already have some functions, for example this one to write data to the serial port, which works perfectly:

bool WriteData(char *buffer, unsigned int nbChar)
{
    DWORD bytesSend;

    //Try to write the buffer on the Serial port
    if(!WriteFile(hSerial, (void *)buffer, nbChar, &bytesSend, 0))
    {
        return false;
    }
    else
        return true;
}

The reading function is like this:

int ReadData(char *buffer, unsigned int nbChar)
{
//Number of bytes we'll have read
DWORD bytesRead;
//Number of bytes we'll really ask to read
unsigned int toRead;

ClearCommError(hSerial, NULL, &status);
//Check if there is something to read
if(status.cbInQue>0)
{
    //If there is we check if there is enough data to read the required number
    //of characters, if not we'll read only the available characters to prevent
    //locking of the application.
    if(status.cbInQue>nbChar)
    {
        toRead = nbChar;
    }
    else
    {
        toRead = status.cbInQue;
    }

    //Try to read the require number of chars, and return the number of read bytes on success
    if(ReadFile(hSerial, buffer, toRead, &bytesRead, NULL) && bytesRead != 0)
    {
        return bytesRead;
    }

}

//If nothing has been read, or that an error was detected return -1
return -1;

}

And no matter what I do with the arduino, this function always returns -1, I even tried loading a code that constantly writes a character to the serial port, but nothing.

I got the functions from here: http://playground.arduino.cc/Interfacing/CPPWindows

so my functions are basically the same. I just copied them into my code instead of using them as classes objects, but more than that it's the same.

So that's my problem, I can write data to the serial but I can't read, what can I try?

Answer 1

For anyone interested, I already solved it and it was a silly mistake. I programmed the Arduino so it would wait for a serial input before sending anything. The computer program writes and sends one line of code after another, and I guess a i7 is faster than the Atmel... and obviously the data takes some time.

Adding a Sleep(10); before reding the port from the computer was enough to finally read the data.

Thanks to @Matts for his help.