Ubuntu C ++ termios.h example program

I've searched a lot and tried many different ways, but I can't seem to send data to gtkterm over a virtual serial bridge (for testing!).

My idea is to contact Atmega uC later, but first I wanted to test the serial communication by setting up a virtual serial bridge using soccat and controlling the output serial port with gtkterm. The problem is I just get useless stuff in gtkterm ... (see screenshots)

Soccat command:

socat -d -d PTY: PTY:

      

        
        
        
      

    

The soccat virtual serial port bridge looks ok because I can send data from one serial terminal to another ...

Gtkterm port settings:

Port: /dev/pts/6
Baudrate: 9600
Parity: none
Bits: 8
Stopbits: 1
Flow control: none

      

        
        
        
      

    

My little GUI compiles and works fine, with an input path "/ dev / pts / 6" and an input speed of 9600. The program works fine, but in gtkterm there are only question marks and squares with symbols in each corner suitable. Let's say it is not interpretable and sign independent as input, BUT the output lengths in gtkterm vary with the length of the input (the number of characters I entered).

Finally, here's my code:

main.cpp:

#include <iostream>
#include "serial/serial_communication.cpp"

std::string inputStringUser = "";
int inputIntUser = 0;
std::string pathSerial = "/dev/...";
int baudrate = 19200;

int main()
{
    std::cout << "main() [communication_serial_uC] started..." <<        std::endl;

    //GETTING STARTED
    std::cout << "Use default port? " << pathSerial << " (Yes = y/ change port = insert the new path" << std::endl;
    std::cin >> inputStringUser;
    if(inputStringUser != "y" && inputStringUser != "Y")
        pathSerial = inputStringUser;
    std::cout << "Serial Port is set to: " + pathSerial << std::endl;

    std::cout << "Use default baudrate? " << baudrate << "Yes = 0/     change baudrate = insert new baudrate" << std::endl;
    std::cin >> inputIntUser;

    if(inputIntUser > 0)
        baudrate = inputIntUser;
    std::cout << "Baudrate is set to: " << baudrate << std::endl;

    Serial_communication myPort(pathSerial, baudrate);

    //OPEN/ CONFIGURATE PORT
    if(myPort.openPort(pathSerial, baudrate) < 0)
    {
        std::cout << "Error: opening" << std::endl;
        return -1;
    }

    //WRITE PORT
    std::cout << "Insert your 'message': (exit = 'exit')" << std::endl;
    std::cin >> inputStringUser;
    while(inputStringUser != "exit")
    {
        if(myPort.sendPort(inputStringUser) < 0)
        {
            std::cout << "Error: sending" << std::endl;
            return -1;
        }
        std::cout << "Insert your 'message': (exit = 'exit')" << std::endl;
        std::cin >> inputStringUser;
    }

    //CLOSE PORT
    if(myPort.closePort() < 0)
    {
        std::cout << "Error: closing" << std::endl;
        return -1;
    }

    std::cout << "main() [communication_serial_uC] beendet..." << std::endl;
    return 0;
}

      

        
        
        
      

    

serial / serial_communication.hpp:

#include <iostream>
#include <string>
#include <cstring>
#include <fcntl.h>
#include <termios.h>

class Serial_communication{

    public:
        Serial_communication(std::string paramPathSerial, int paramBaudrate);
        ~Serial_communication();

        int openPort(std::string pathSerial, int baudrate);
        int sendPort(std::string testString);
        int closePort();

    private:
        std::string pathSerial;
        int baudrate;

        //filedescriptors
        int fd;
};

      

        
        
        
      

    

serial / serial_communcation.cpp

#include <iostream>

#include "serial_communication.h"

Serial_communication::Serial_communication(std::string paramPathSerial, int paramBaudrate)
{
    fd = 0;
    pathSerial = paramPathSerial;
    baudrate = paramBaudrate;
}

Serial_communication::~Serial_communication()
{
}

int Serial_communication::openPort(std::string pathSerial, int baudrate)
{
    std::cout << "openPort() [serial_communication] started with the following paramters... pathSerial = " << pathSerial << ", baudrate = " << baudrate << std::endl;

    //OPENING PORT

    //open serial port
    fd = open(pathSerial.c_str(), O_RDWR | O_NOCTTY | O_NDELAY);
    if(fd < 0)
    {
        std::cout << "Error [serial_communcation]: opening Port: " << pathSerial << std::endl;
        return -1;
    }

    //struct termios
    struct termios serial, serial_old;

    //get parameters associated with the terminal
    if(tcgetattr(fd, &serial) < 0)
    {
        std::cout << "Error [serial_communication]: getting configuration" << std::endl;
        return -1;
    }

    //safe old parameters
    serial_old = serial;

    std::cout << "[serial_communication]: Port opened" << std::endl;
    //SERIAL CONFIGURATION
    /* Set Baud Rate */
    cfsetospeed (&serial, (speed_t)baudrate);
    cfsetispeed (&serial, (speed_t)baudrate);

//     Setting other Port Stuff
    serial.c_cflag     &=  ~PARENB;            // Make 8n1
    serial.c_cflag     &=  ~CSTOPB;
    serial.c_cflag     &=  ~CSIZE;
    serial.c_cflag     |=  CS8;

    serial.c_cflag     &=  ~CRTSCTS;           // no flow control
    serial.c_cc[VMIN]   =  1;                  // read doesn't block
    serial.c_cc[VTIME]  =  5;                  // 0.5 seconds read timeout
    serial.c_cflag     |=  CREAD | CLOCAL;     // turn on READ & ignore ctrl lines



    /* Make raw */
    cfmakeraw(&serial);

    /* Flush Port, then applies attributes */
    tcflush( fd, TCIFLUSH );

    //set attributes to port
    if(tcsetattr(fd, TCSANOW, &serial) < 0)
    {
        std::cout << "Error [serial_communication]: set attributes" << std::endl;
        return -1;
    }

    //CONFIGURATION FINISHED
    std::cout << "openPort() [serial_communication] finished..." << std::endl;
    return 1;
}

int Serial_communication::sendPort(std::string textString)
{
    std::cout << "write() [Serial_communication] started with the following parameter... textString = " << textString << std::endl;
    //attempt to send
    if(write(fd, &textString, std::strlen(textString.c_str())) < 0)
    {
        std::cout << "Error [serial_communcation]: write";
        return -1;
    }

    //SENDING FINISHED
    std::cout << "write() [serial_communcation] finished..." << std::endl;
    return 1;
}

int Serial_communication::closePort()
{
    close(fd);
    return 1;
}

      

        
        
        
      

    

So ... that's all I have. I tried my best and joined information from many websites and tried many code examples. My problem is I don't even know where to look, so I appreciate any hint ... If you have any questions or information, please let me know!

Thanks in advance Thorben

BTW: I AM NOT THAT CASE WITH C ++ and I'm open to comments about my style, but that shouldn't be the main issue ...