void ttyO2_signal_handler_IO (int status) {
//handle_RX_header() and handle_RX_payload() private variables moved to privates of each ttyO signal handler.
    static struct _sRxSignalData    ttyO2_status = {2, {0, 0, 0, 0, 0, 0}};
    static sMsgData ttyO2_RX_msg;
//mutex was used to stop signal handling while other is not finished. 
    pthread_mutex_lock(&ttyO2_mutex);
//should stop errors - probably working didn't happined after changes, not sure if becouse of mutex or this
    ioctl(UART_port_ttyO2, REAL_FIONBIO, 1);
//should stop other signals in peripheral - wasn't working
    ioctl(UART_port_ttyO2, FIOASYNC, 0);
    signal_handler_IO(UART_port_ttyO2, &ttyO2_status, &ttyO2_RX_msg);
    ioctl(UART_port_ttyO2, REAL_FIONBIO, 0);
    ioctl(UART_port_ttyO2, FIOASYNC, 1);
    pthread_mutex_unlock(&ttyO2_mutex);
}

void setup_port(int port_nr) {
    struct termios  options;
    int             port = port_nr_to_fd(port_nr);
    if (port < 0) {
        printf("Request to set-up invalid port(%d) detected...\n", port_nr);
    }
            /* get the current options */
    tcgetattr(port, &options);
            /* Set the to 57600kbps baud rate 8N1*/
    cfsetispeed(&options, B57600);
    cfsetospeed(&options, B57600);
    options.c_cflag &= ~(PARENB | CSTOPB | CSIZE);
    options.c_cflag |= CS8;    /* Select 8 data bits */
            /* set raw input, 1 second timeout */
    options.c_cflag     |= (CLOCAL | CREAD);
    options.c_lflag     &= ~(ICANON | ECHO | ECHOE);
    options.c_oflag     &= ~OPOST;
//mess with '\n' and '\r' characters on data receive fix, break symbol should be ok too.
    options.c_iflag     &= ~(IXOFF | IXON | IGNBRK | INLCR | IGNCR | ICRNL);
    options.c_cc[VMIN]  = 0;
    options.c_cc[VTIME] = 0;
            /* set the options */
    tcsetattr(port, TCSANOW, &options);
}