在Ubuntu 12.04 ros hydro上运行代码时串口停止，需要重启才能重新启动

Question

我们有一个代码可以向motordriver发送一些消息。 我们用cpp代码创建了一个ROS节点（如下）。 代码可以工作，但一段时间后串口被杀死了。 如果我们尝试重新启动节点，则无法重新打开串行端口。 我们还尝试用CuteCom（终端）打开端口。但CuteCom也不能打开这个端口。 我们用不同的库（termios.h和SerialStream.h）创建了代码，但它们给出了相同的错误。 我们已经看过Linux（dmesg）的日志文件。在我们再次运行节点后，会出现如下错误：LSR安全检查已启用。

我们无法找到问题所在。希望有人可以帮助我们。

#include <SerialStream.h>
#include <iostream>
#include <unistd.h>
#include <cstdlib>
#include <string>

#include "ros/ros.h"

using namespace std;
using namespace LibSerial;

int main(int argc, char **argv  )
{
    //initialize ROS
    ros::init(argc, argv, "uart");

    //define a nodehandle and define the rate for the "ros while loop"
    ros::NodeHandle nh;
    ros::Rate rate(100);

    ROS_INFO("Ros is initialized");


    //
     // Open the serial port.
    //
     SerialStream serial_port;
     char c;
     ROS_DEBUG("Serial Port will be opened");
     serial_port.Open("/dev/ttyS8") ;
    //check if serial port opens correctly
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not open serial port.");
        return(1);
     }

    ROS_INFO("Serial port is opened");

     //
     // Set the baud rate of the serial port.
     //
     serial_port.SetBaudRate( SerialStreamBuf::BAUD_115200 ) ;
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not set the baud rate.");
        return(1) ;
     }
    ROS_INFO("baud rate is setted");

     //
     // Set the number of data bits.
     //
     serial_port.SetCharSize( SerialStreamBuf::CHAR_SIZE_8 ) ;
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not set the character size.");
        return(1) ;
     }
    ROS_INFO("char size is setted");

     //
     // Disable parity.
     //
     serial_port.SetParity( SerialStreamBuf::PARITY_NONE ) ;
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not disable the parity.");
        return(1) ;
     }

    ROS_INFO("parity is setted");
     //
     // Set the number of stop bits.
     //
     serial_port.SetNumOfStopBits( 2 ) ;
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not set the number of stop bits.");
        return(1) ;
     }
    ROS_INFO("stop bits are setted");

     //
     // Turn off hardware flow control.
     //
     serial_port.SetFlowControl( SerialStreamBuf::FLOW_CONTROL_NONE ) ;
     if ( ! serial_port.good() )
     {
        ROS_ERROR("Error: Could not use hardware flow control.");
        return(1) ;
     } 
    ROS_INFO("Disabled flow control");

     //
     // Do not skip whitespace characters while reading from the
     // serial port.
     //
     // serial_port.unsetf( std::ios_base::skipws ) ;
     //
     // Wait for some data to be available at the serial port.
     //
     //
     // Keep reading data from serial port and print it to the screen.
     //
     // Wait for some data to be available at the serial port.


  //
  //    while( serial_port.rdbuf()->in_avail() > 0 )

    while(ros::ok())
     {
        char out_buf[8];

        //Define data
        out_buf[0] = 0x5a;
        out_buf[1] = 0xaa;
        out_buf[2] = 0x03;
        out_buf[3] = 0x20;
        out_buf[4] = 0x00;
        out_buf[5] = 0x00;
        out_buf[6] = 0x00;
        out_buf[7] = 0x00;

        //write data to serial port.
        if(serial_port.IsOpen()){
            ROS_INFO("1");
                serial_port.write(out_buf, 8);
            ROS_INFO("2");
            //serial_port.writechar
        } else{
            ROS_ERROR("Serial port is closed");
        }

        ROS_INFO_ONCE("We doen het");
            rate.sleep();
     }

    serial_port.Close();
    ROS_INFO("serial port is closed");

//     while(1)
//     {
//         char next_byte;
//         serial_port.get(next_byte);  HERE I RECEIVE THE FIRST ANSWER
//         std::cerr << next_byte;
//
//     }

     return EXIT_SUCCESS ;

}