Question

我即将编写一个c ++ GUI应用程序（wxWidgets）来控制Arduino。我想使用Arduino游乐场网站（http://playground.arduino.cc/Interfacing/CPPWindows）中的SerialClass.h和SerialClass.cpp。我已经使用这些.h和.cpp文件构建了一个控制台应用程序，它运行正常。最近，我以某种方式得到一个奇怪的错误信息：

在构造函数Serial::Serial(char*)

中

错误：无法转换＆＃39; char *＆＃39; to const＃WCHAR *＆＃39;争论＆＃39; 1＆＃39; to＆＃39; void * CreateFileW（const WCHAR *，DWORD，DWORD，_SECURITY_ATTRIBUTES *，DWORD，DWORD，void *）＆＃39;

我没有收到这条消息。在SerialClass.h或SerialClass.cpp中应该更改什么才能使它工作？ Arduino代码很好。为了完整性，我附加了控制台应用程序的c ++代码。很多google-fu无济于事。

#include <stdio.h>
#include <tchar.h>
#include "SerialClass.h"    // Library described above
#include <string>
#include <iostream>

using namespace std;
bool weiter = true;
int dummy1 = 0;

int _tmain(int argc, _TCHAR* argv[]) {
cout << "*** This is my Arduino LED app! ***\n" << endl;
//Serial* SP = new Serial("COM4");
//Serial serial("COM4");
Serial serial("COM4");

if (serial.IsConnected())
//printf("We are connected\n");
cout << "We are connected!\n" << endl;

while (weiter == true) {

cout << "Press 1 for LED on; press 0 for LED off!" << endl;
cin >> dummy1;
if (dummy1 == 1) {

if (serial.IsConnected()){
    serial.WriteData("o",1);
    cout << "LED is on!" << endl;
    cout << "Do you want to continue? 1 for continue, 0 for exit!" << endl;
    //printf("\nData sent successfully!\n");
     cin >> weiter;
    }
   }
else {
    serial.WriteData("p", 1 );
    cout << "LED is off!" << endl;
    cout << "Do you want to continue? 1 for continue, 0 for exit!" << endl;
    cin >> weiter;
  }
 }

if (weiter == 1)
{
    weiter = true;
}

if (weiter == 0) {
    weiter = false;
return 0;
  }
}

编辑：这是SerialClass.h和Serial.cpp的代码：

#include "SerialClass.h"
Serial::Serial(char *portName)
{
//We're not yet connected
this->connected = false;

//Try to connect to the given port throuh CreateFile
this->hSerial = CreateFile(portName,
        GENERIC_READ | GENERIC_WRITE,
        0,
        NULL,
        OPEN_EXISTING,
        FILE_ATTRIBUTE_NORMAL,
        NULL);

  //Check if the connection was successfull
  if(this->hSerial==INVALID_HANDLE_VALUE)
  {
    //If not success full display an Error
    if(GetLastError()==ERROR_FILE_NOT_FOUND){

        //Print Error if neccessary
        printf("ERROR: Handle was not attached. Reason: %s not available.\n", portName);

    }
    else
    {
        printf("ERROR!!!");
    }
  }
   else
 {
    //If connected we try to set the comm parameters
    DCB dcbSerialParams = {0};

    //Try to get the current
    if (!GetCommState(this->hSerial, &dcbSerialParams))
    {
        //If impossible, show an error
        printf("failed to get current serial parameters!");
    }
    else
    {
        //Define serial connection parameters for the arduino board
        dcbSerialParams.BaudRate=CBR_9600;
        dcbSerialParams.ByteSize=8;
        dcbSerialParams.StopBits=ONESTOPBIT;
        dcbSerialParams.Parity=NOPARITY;
        //Setting the DTR to Control_Enable ensures that the Arduino is properly
        //reset upon establishing a connection
        dcbSerialParams.fDtrControl = DTR_CONTROL_ENABLE;

         //Set the parameters and check for their proper application
         if(!SetCommState(hSerial, &dcbSerialParams))
         {
            printf("ALERT: Could not set Serial Port parameters");
         }
         else
         {
             //If everything went fine we're connected
             this->connected = true;
             //Flush any remaining characters in the buffers
             PurgeComm(this->hSerial, PURGE_RXCLEAR | PURGE_TXCLEAR);
             //We wait 2s as the arduino board will be reseting
             Sleep(ARDUINO_WAIT_TIME);
         }
    }
}

}

这是SerialClass.h：

#ifndef SERIALCLASS_H_INCLUDED
#define SERIALCLASS_H_INCLUDED

#define ARDUINO_WAIT_TIME 2000

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>

class Serial
{
private:
    //Serial comm handler
    HANDLE hSerial;
    //Connection status
    bool connected;
    //Get various information about the connection
    COMSTAT status;
    //Keep track of last error
    DWORD errors;

public:
    //Initialize Serial communication with the given COM port
    Serial(char *portName);
    //Close the connection
    ~Serial();
    //Read data in a buffer, if nbChar is greater than the
    //maximum number of bytes available, it will return only the
    //bytes available. The function return -1 when nothing could
    //be read, the number of bytes actually read.
    int ReadData(char *buffer, unsigned int nbChar);
    //Writes data from a buffer through the Serial connection
    //return true on success.
    bool WriteData(char *buffer, unsigned int nbChar);
    //Check if we are actually connected
    bool IsConnected();
};

#endif // SERIALCLASS_H_INCLUDED

Answer 1

Serial serial("COM4");

该行传递char *。要传递WCHAR *，您需要将其更改为：

Serial serial(L"COM4");

Answer 2

构造函数中的CreateFile（）函数需要一个const WCHAR *，因此您需要将const char *转换为const wchar *。

here是进行转化的帖子。

虽然我没有太多关于此的信息，但该帖子描述了几种方法，其中一个是：

   char *p="D:\\"; //just for proper syntax highlighting ..."
   const WCHAR *pwcsName;
   // required size
   int nChars = MultiByteToWideChar(CP_ACP, 0, p, -1, NULL, 0);
   // allocate it
   pwcsName = new WCHAR[nChars];
   MultiByteToWideChar(CP_ACP, 0, p, -1, (LPWSTR)pwcsName, nChars);
  // use it....

  // delete it
delete [] pwcsName;

}

错误消息：c ++ GUI和Arduino之间的串行通信

2 个答案: