C ++与Arduino的串行通信

时间:2016-10-19 10:00:37

标签: c++ serialization

我正在开发一个在Windows PC和Arduino Uno卡之间进行串行通信的项目。

在C ++代码中,我有一个SerialClass.h和一个Serial.cpp

我的问题是我遇到编译器错误:标识符" SP"未定义 在函数中

void Serial::SendtoArd(int val, int var)
{

if (SP->IsConnected())
{
    bool writeData = false;
    writeData = SP->WriteData("test",4);
}

我知道如果我在这个函数中定义SP我就摆脱了这个错误,但是 我不想激活该功能中的串行端口。我想激活此功能中的串口

bool Serial::OpenPtoArd()

{

Serial* SP = new Serial("\\\\.\\COM3");    // adjust as needed
if (SP->IsConnected())
{

    bool status = true;
}
}

并在我的应用程序运行时保持活动状态。

有人可以帮助我吗?

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();
bool OpenPtoArd();
void SendtoArd(int val, int var);


};

这是Serial.cpp

#endif // SERIALCLASS_H_INCLUDED


#include "stdafx.h"
#include "SerialClass.h"


#define LEN 1
bool status = false;
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;

        //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;
            //We wait 2s as the arduino board will be reseting
            Sleep(ARDUINO_WAIT_TIME);
        }
    }
}

}

Serial::~Serial()
{
//Check if we are connected before trying to disconnect
if (this->connected)
{
    //We're no longer connected
    this->connected = false;
    //Close the serial handler
    CloseHandle(this->hSerial);
}
}

int Serial::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;

//Use the ClearCommError function to get status info on the Serial port
ClearCommError(this->hSerial, &this->errors, &this->status);

//Check if there is something to read
if (this->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 (this->status.cbInQue>nbChar)
    {
        toRead = nbChar;
    }
    else
    {
        toRead = this->status.cbInQue;
    }

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

}

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

}


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

//Try to write the buffer on the Serial port
if (!WriteFile(this->hSerial, (void *)buffer, nbChar, &bytesSend, 0))
{
    //In case it don't work get comm error and return false
    ClearCommError(this->hSerial, &this->errors, &this->status);

    return false;
}
else
    return true;
}

bool Serial::IsConnected()
{
//Simply return the connection status
return this->connected;
}



void readme()

{

Serial serial("COM3");

char c[LEN + 1];
int numBytes = 0;
while (true)
{
    numBytes = serial.ReadData(c, LEN);
    if (numBytes != -1)
    {
        // Terminate the string if we want to use c variable as a string
        c[numBytes] = 0;
        break;
    }
}

}

bool Serial::OpenPtoArd()

{

Serial* SP = new Serial("\\\\.\\COM3");    // adjust as needed
if (SP->IsConnected())
{

    bool status = true;
}
}

void Serial::SendtoArd(int val, int var)
{

if (SP->IsConnected())
{
    bool writeData = false;
    writeData = SP->WriteData("test",4);
}

}

1 个答案:

答案 0 :(得分:0)

此代码的问题

bool Serial::OpenPtoArd()
{
    Serial* SP = new Serial("\\\\.\\COM3");    // adjust as needed
    if (SP->IsConnected())
    {
        bool status = true;
    }
}

是你正在创建新的Serial - 然后在函数退出时丢失指向Serial的指针。如果您希望其他功能能够访问它,则需要SP变量 之外 OpenPtoArd()函数。

您可以(应该?)让它成为您班级的成员(顺便说一下 与Arduino的Serial班级冲突 - 称之为else!),或使其成为全局变量:将以下行放在文件顶部附近:

YourSerialClass *SP = NULL;

请注意,我将变量设置为NULL。您的其他代码需要知道是否已创建SP端口 - 并且使用它(如果尚未使用):

if ((SP!=NULL) && (SP->IsConnectd()) {
    ... do SP things
} // if