SerialIO.cpp

Go to the documentation of this file.

/****************************************************************
 *
 * Copyright (c) 2010
 *
 * Fraunhofer Institute for Manufacturing Engineering   
 * and Automation (IPA)
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Project name: care-o-bot
 * ROS stack name: cob_driver
 * ROS package name: cob_relayboard
 * Description: Class for general Serial communication under Linux OS.
 *                                                              
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *                      
 * Author: Philipp Koehler
 * Supervised by: Christian Connette, email:christian.connette@ipa.fhg.de
 *
 * Date of creation: March 2010
 * ToDo:
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Fraunhofer Institute for Manufacturing 
 *       Engineering and Automation (IPA) nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License LGPL as 
 * published by the Free Software Foundation, either version 3 of the 
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License LGPL for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public 
 * License LGPL along with this program. 
 * If not, see <http://www.gnu.org/licenses/>.
 *
 ****************************************************************/

//#include "stdafx.h"
#include <../include/SerialIO.h>
#include <math.h>
#include <string.h>
#include <iostream>

#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/serial.h>
#include <unistd.h>
#include <termios.h>


bool getBaudrateCode(int iBaudrate, int* iBaudrateCode)
{
        // baudrate codes are defined in termios.h
        // currently upto B1000000
        const int baudTable[] = {
                0, 50, 75, 110, 134, 150, 200, 300, 600,
                1200, 1800, 2400, 4800,
                9600, 19200, 38400, 57600, 115200, 230400,
                460800, 500000, 576000, 921600, 1000000
        };
        const int baudCodes[] = {
                B0, B50, B75, B110, B134, B150, B200, B300, B600,
                B1200, B1800, B2400, B4800,
                B9600, B19200, B38400, B57600, B115200, B230400,
                B460800, B500000, B576000, B921600, B1000000
        };
        const int iBaudsLen = sizeof(baudTable) / sizeof(int);

        bool ret = false;
        *iBaudrateCode = B38400;
        int i;
        for( i=0; i<iBaudsLen; i++ ) {
                if( baudTable[i] == iBaudrate ) {
                        *iBaudrateCode = baudCodes[i];
                        ret = true;
                        break;
                }
        }
        
        return ret;
}




// Konstruktion/Destruktion

SerialIO::SerialIO()
        : m_DeviceName("/dev/ttyUSB0"),
          m_Device(-1),
          m_BaudRate(9600),
          m_Multiplier(1.0),
          m_ByteSize(8),
          m_StopBits(SB_ONE),
          m_Parity(PA_NONE),
          m_Handshake(HS_NONE),
          m_ReadBufSize(1024),
          m_WriteBufSize(m_ReadBufSize),
          m_Timeout(0),
          m_ShortBytePeriod(false)
{
        m_BytePeriod.tv_sec = 0;
        m_BytePeriod.tv_usec = 0;
}

SerialIO::~SerialIO()
{
        closeIO();
}

int SerialIO::openIO()
{
        int Res;
        // open device
        m_Device = open(m_DeviceName.c_str(), O_RDWR | O_NOCTTY | O_NONBLOCK);

        if(m_Device < 0)
        {       
                //RF_ERR("Open " << m_DeviceName << " failed, error code " << errno);
                std::cout << "Trying to open " << m_DeviceName << " failed: "
                        << strerror(errno) << " (Error code " << errno << ")";

                return -1;
        }

        // set parameters
        Res = tcgetattr(m_Device, &m_tio);
        if (Res == -1)
        {
                std::cerr << "tcgetattr of " << m_DeviceName << " failed: "
                        << strerror(errno) << " (Error code " << errno << ")\n";

                close(m_Device);
                m_Device = -1;

                return -1;
        }

        // Default values
        m_tio.c_iflag = 0;
        m_tio.c_oflag = 0;
        m_tio.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
        m_tio.c_lflag = 0;
        cfsetispeed(&m_tio, B9600);
        cfsetospeed(&m_tio, B9600);

        m_tio.c_cc[VINTR] = 3;  // Interrupt
        m_tio.c_cc[VQUIT] = 28; // Quit
        m_tio.c_cc[VERASE] = 127;       // Erase
        m_tio.c_cc[VKILL] = 21; // Kill-line
        m_tio.c_cc[VEOF] = 4;   // End-of-file
        m_tio.c_cc[VTIME] = 0;  // Time to wait for data (tenths of seconds)
        m_tio.c_cc[VMIN] = 1;   // Minimum number of characters to read
        m_tio.c_cc[VSWTC] = 0;
        m_tio.c_cc[VSTART] = 17;
        m_tio.c_cc[VSTOP] = 19;
        m_tio.c_cc[VSUSP] = 26;
        m_tio.c_cc[VEOL] = 0;   // End-of-line
        m_tio.c_cc[VREPRINT] = 18;
        m_tio.c_cc[VDISCARD] = 15;
        m_tio.c_cc[VWERASE] = 23;
        m_tio.c_cc[VLNEXT] = 22;
        m_tio.c_cc[VEOL2] = 0;  // Second end-of-line


        // set baud rate
        int iNewBaudrate = int(m_BaudRate * m_Multiplier + 0.5);
        std::cerr << "Setting Baudrate to " << iNewBaudrate << "\n";

        int iBaudrateCode = 0;
        bool bBaudrateValid = getBaudrateCode(iNewBaudrate, &iBaudrateCode);
        
        cfsetispeed(&m_tio, iBaudrateCode);
        cfsetospeed(&m_tio, iBaudrateCode);

        if( !bBaudrateValid ) {
                std::cerr << "Baudrate code not available - setting baudrate directly\n";
                struct serial_struct ss;
                ioctl( m_Device, TIOCGSERIAL, &ss );
                ss.flags |= ASYNC_SPD_CUST;
                ss.custom_divisor = ss.baud_base / iNewBaudrate;
                ioctl( m_Device, TIOCSSERIAL, &ss );
        }


        // set data format
        m_tio.c_cflag &= ~CSIZE;
        switch (m_ByteSize)
        {
                case 5:
                        m_tio.c_cflag |= CS5;
                        break;
                case 6:
                        m_tio.c_cflag |= CS6;
                        break;
                case 7:
                        m_tio.c_cflag |= CS7;
                        break;
                case 8:
                default:
                        m_tio.c_cflag |= CS8;
        }

        m_tio.c_cflag &= ~ (PARENB | PARODD);

        switch (m_Parity)
        {
                case PA_ODD:
                        m_tio.c_cflag |= PARODD;
                        //break;  // break must not be active here as we need the combination of PARODD and PARENB on odd parity.
                        
                case PA_EVEN:
                        m_tio.c_cflag |= PARENB;
                        break;
                        
                case PA_NONE:
                default: {}
        }
        
        switch (m_StopBits)
        {
                case SB_TWO:
                        m_tio.c_cflag |= CSTOPB;
                        break;
                        
                case SB_ONE:
                default:
                        m_tio.c_cflag &= ~CSTOPB;
        }

        // hardware handshake
        switch (m_Handshake)
        {
                case HS_NONE:
                        m_tio.c_cflag &= ~CRTSCTS;
                        m_tio.c_iflag &= ~(IXON | IXOFF | IXANY);
                        break;
                case HS_HARDWARE:
                        m_tio.c_cflag |= CRTSCTS;
                        m_tio.c_iflag &= ~(IXON | IXOFF | IXANY);
                        break;
                case HS_XONXOFF:
                        m_tio.c_cflag &= ~CRTSCTS;
                        m_tio.c_iflag |= (IXON | IXOFF | IXANY);
                        break;
        }

        m_tio.c_oflag &= ~OPOST;
        m_tio.c_lflag &= ~ICANON;

        // write parameters
        Res = tcsetattr(m_Device, TCSANOW, &m_tio);

        if (Res == -1)
        {
                std::cerr << "tcsetattr " << m_DeviceName << " failed: "
                        << strerror(errno) << " (Error code " << errno << ")\n";

                close(m_Device);
                m_Device = -1;

                return -1;
        }

        // set buffer sizes
//      SetupComm(m_Device, m_ReadBufSize, m_WriteBufSize);

        // set timeout
        setTimeout(m_Timeout);

        return 0;
}

void SerialIO::closeIO()
{
        if (m_Device != -1)
        {
                close(m_Device);
                m_Device = -1;
        }
}

void SerialIO::setTimeout(double Timeout)
{
        m_Timeout = Timeout;
        if (m_Device != -1)
        {
                m_tio.c_cc[VTIME] = cc_t(ceil(m_Timeout * 10.0));
                tcsetattr(m_Device, TCSANOW, &m_tio);
        }

}

void SerialIO::setBytePeriod(double Period)
{
        m_ShortBytePeriod = false;
        m_BytePeriod.tv_sec = time_t(Period);
        m_BytePeriod.tv_usec = suseconds_t((Period - m_BytePeriod.tv_sec) * 1000);
}

//-----------------------------------------------
void SerialIO::changeBaudRate(int iBaudRate)
{
        /*
        int iRetVal;

        m_BaudRate = iBaudRate;

        int iNewBaudrate = int(m_BaudRate * m_Multiplier + 0.5);
        int iBaudrateCode = getBaudrateCode(iNewBaudrate);
        cfsetispeed(&m_tio, iBaudrateCode);
        cfsetospeed(&m_tio, iBaudrateCode);
        
        iRetVal = tcsetattr(m_Device, TCSANOW, &m_tio);
        if(iRetVal == -1)
        {
                LOG_OUT("error in SerialCom::changeBaudRate()");
                char c;
                std::cin >> c;
                exit(0);
        }*/
}


int SerialIO::readBlocking(char *Buffer, int Length)
{
        ssize_t BytesRead;
        BytesRead = read(m_Device, Buffer, Length);

        return BytesRead;
}

int SerialIO::readNonBlocking(char *Buffer, int Length)
{
        int iAvaibleBytes = getSizeRXQueue();
        int iBytesToRead = (Length < iAvaibleBytes) ? Length : iAvaibleBytes;
        ssize_t BytesRead;


        BytesRead = read(m_Device, Buffer, iBytesToRead);

        return BytesRead;
}

int SerialIO::writeIO(const char *Buffer, int Length)
{
        ssize_t BytesWritten;

        if (m_BytePeriod.tv_usec || m_BytePeriod.tv_sec)
        {
                int i;
                for (i = 0; i < Length; i++)
                {
                        BytesWritten = write(m_Device, Buffer + i, 1);
                        if (BytesWritten != 1)
                                break;
                        select(0, 0, 0, 0, &m_BytePeriod);
                }
                BytesWritten = i;
        }
        else
                BytesWritten = write(m_Device, Buffer, Length);

}

int SerialIO::getSizeRXQueue()
{
        int cbInQue;
        int Res = ioctl(m_Device, FIONREAD, &cbInQue);
        if (Res == -1) {
                return 0;
        }
        return cbInQue;
}