Gary Servin / ros_lib_jade

ROS Serial library for Mbed platforms for ROS Jade Turtle. Check http://wiki.ros.org/rosserial_mbed/ for more information.

Dependencies:   BufferedSerial

Dependents:   rosserial_mbed_hello_world_publisher_jade

ROSSerial_mbed for Jade Distribution

The Robot Operating System (ROS) is a flexible framework for writing robot software. It is a collection of tools, libraries, and conventions that aim to simplify the task of creating complex and robust robot behavior across a wide variety of robotic platforms.

The rosserial_mbed package allows to write ROS nodes on any mbed enabled devices and have them connected to a running ROS system on your computer using the serial port.

Hello World (example publisher)

Import programrosserial_mbed_hello_world_publisher_jade

rosserial_mbed Hello World example for jade distribution

Last commit 19 Apr 2016 by Gary Servin

Running the Code

Now, launch the roscore in a new terminal window:

Quote:

$ roscore

Next, run the rosserial client application that forwards your MBED messages to the rest of ROS. Make sure to use the correct serial port:

Quote:

$ rosrun rosserial_python serial_node.py /dev/ttyACM0

Finally, watch the greetings come in from your MBED by launching a new terminal window and entering :

Quote:

$ rostopic echo chatter

See Also

More examples

Blink

/*
 * rosserial Subscriber Example
 * Blinks an LED on callback
 */
#include "mbed.h"
#include <ros.h>
#include <std_msgs/Empty.h>

ros::NodeHandle nh;
DigitalOut myled(LED1);

void messageCb(const std_msgs::Empty& toggle_msg){
    myled = !myled;   // blink the led
}

ros::Subscriber<std_msgs::Empty> sub("toggle_led", &messageCb);

int main() {
    nh.initNode();
    nh.subscribe(sub);

    while (1) {
        nh.spinOnce();
        wait_ms(1);
    }
}

Push

/*
 * Button Example for Rosserial
 */

#include "mbed.h"
#include <ros.h>
#include <std_msgs/Bool.h>

PinName button = p20;

ros::NodeHandle nh;

std_msgs::Bool pushed_msg;
ros::Publisher pub_button("pushed", &pushed_msg);

DigitalIn button_pin(button);
DigitalOut led_pin(LED1);

bool last_reading;
long last_debounce_time=0;
long debounce_delay=50;
bool published = true;

Timer t;
int main() {
    t.start();
    nh.initNode();
    nh.advertise(pub_button);

    //Enable the pullup resistor on the button
    button_pin.mode(PullUp);

    //The button is a normally button
    last_reading = ! button_pin;

    while (1) {
        bool reading = ! button_pin;

        if (last_reading!= reading) {
            last_debounce_time = t.read_ms();
            published = false;
        }

        //if the button value has not changed for the debounce delay, we know its stable
        if ( !published && (t.read_ms() - last_debounce_time)  > debounce_delay) {
            led_pin = reading;
            pushed_msg.data = reading;
            pub_button.publish(&pushed_msg);
            published = true;
        }

        last_reading = reading;

        nh.spinOnce();
    }
}

rosgraph_msgs/Log.h

Committer:
garyservin
Date:
2016-03-31
Revision:
0:a906bb7c7831

File content as of revision 0:a906bb7c7831:

#ifndef _ROS_rosgraph_msgs_Log_h
#define _ROS_rosgraph_msgs_Log_h

#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include "ros/msg.h"
#include "std_msgs/Header.h"

namespace rosgraph_msgs
{

  class Log : public ros::Msg
  {
    public:
      std_msgs::Header header;
      int8_t level;
      const char* name;
      const char* msg;
      const char* file;
      const char* function;
      uint32_t line;
      uint8_t topics_length;
      char* st_topics;
      char* * topics;
      enum { DEBUG = 1  };
      enum { INFO = 2   };
      enum { WARN = 4   };
      enum { ERROR = 8  };
      enum { FATAL = 16  };

    Log():
      header(),
      level(0),
      name(""),
      msg(""),
      file(""),
      function(""),
      line(0),
      topics_length(0), topics(NULL)
    {
    }

    virtual int serialize(unsigned char *outbuffer) const
    {
      int offset = 0;
      offset += this->header.serialize(outbuffer + offset);
      union {
        int8_t real;
        uint8_t base;
      } u_level;
      u_level.real = this->level;
      *(outbuffer + offset + 0) = (u_level.base >> (8 * 0)) & 0xFF;
      offset += sizeof(this->level);
      uint32_t length_name = strlen(this->name);
      memcpy(outbuffer + offset, &length_name, sizeof(uint32_t));
      offset += 4;
      memcpy(outbuffer + offset, this->name, length_name);
      offset += length_name;
      uint32_t length_msg = strlen(this->msg);
      memcpy(outbuffer + offset, &length_msg, sizeof(uint32_t));
      offset += 4;
      memcpy(outbuffer + offset, this->msg, length_msg);
      offset += length_msg;
      uint32_t length_file = strlen(this->file);
      memcpy(outbuffer + offset, &length_file, sizeof(uint32_t));
      offset += 4;
      memcpy(outbuffer + offset, this->file, length_file);
      offset += length_file;
      uint32_t length_function = strlen(this->function);
      memcpy(outbuffer + offset, &length_function, sizeof(uint32_t));
      offset += 4;
      memcpy(outbuffer + offset, this->function, length_function);
      offset += length_function;
      *(outbuffer + offset + 0) = (this->line >> (8 * 0)) & 0xFF;
      *(outbuffer + offset + 1) = (this->line >> (8 * 1)) & 0xFF;
      *(outbuffer + offset + 2) = (this->line >> (8 * 2)) & 0xFF;
      *(outbuffer + offset + 3) = (this->line >> (8 * 3)) & 0xFF;
      offset += sizeof(this->line);
      *(outbuffer + offset++) = topics_length;
      *(outbuffer + offset++) = 0;
      *(outbuffer + offset++) = 0;
      *(outbuffer + offset++) = 0;
      for( uint8_t i = 0; i < topics_length; i++){
      uint32_t length_topicsi = strlen(this->topics[i]);
      memcpy(outbuffer + offset, &length_topicsi, sizeof(uint32_t));
      offset += 4;
      memcpy(outbuffer + offset, this->topics[i], length_topicsi);
      offset += length_topicsi;
      }
      return offset;
    }

    virtual int deserialize(unsigned char *inbuffer)
    {
      int offset = 0;
      offset += this->header.deserialize(inbuffer + offset);
      union {
        int8_t real;
        uint8_t base;
      } u_level;
      u_level.base = 0;
      u_level.base |= ((uint8_t) (*(inbuffer + offset + 0))) << (8 * 0);
      this->level = u_level.real;
      offset += sizeof(this->level);
      uint32_t length_name;
      memcpy(&length_name, (inbuffer + offset), sizeof(uint32_t));
      offset += 4;
      for(unsigned int k= offset; k< offset+length_name; ++k){
          inbuffer[k-1]=inbuffer[k];
      }
      inbuffer[offset+length_name-1]=0;
      this->name = (char *)(inbuffer + offset-1);
      offset += length_name;
      uint32_t length_msg;
      memcpy(&length_msg, (inbuffer + offset), sizeof(uint32_t));
      offset += 4;
      for(unsigned int k= offset; k< offset+length_msg; ++k){
          inbuffer[k-1]=inbuffer[k];
      }
      inbuffer[offset+length_msg-1]=0;
      this->msg = (char *)(inbuffer + offset-1);
      offset += length_msg;
      uint32_t length_file;
      memcpy(&length_file, (inbuffer + offset), sizeof(uint32_t));
      offset += 4;
      for(unsigned int k= offset; k< offset+length_file; ++k){
          inbuffer[k-1]=inbuffer[k];
      }
      inbuffer[offset+length_file-1]=0;
      this->file = (char *)(inbuffer + offset-1);
      offset += length_file;
      uint32_t length_function;
      memcpy(&length_function, (inbuffer + offset), sizeof(uint32_t));
      offset += 4;
      for(unsigned int k= offset; k< offset+length_function; ++k){
          inbuffer[k-1]=inbuffer[k];
      }
      inbuffer[offset+length_function-1]=0;
      this->function = (char *)(inbuffer + offset-1);
      offset += length_function;
      this->line =  ((uint32_t) (*(inbuffer + offset)));
      this->line |= ((uint32_t) (*(inbuffer + offset + 1))) << (8 * 1);
      this->line |= ((uint32_t) (*(inbuffer + offset + 2))) << (8 * 2);
      this->line |= ((uint32_t) (*(inbuffer + offset + 3))) << (8 * 3);
      offset += sizeof(this->line);
      uint8_t topics_lengthT = *(inbuffer + offset++);
      if(topics_lengthT > topics_length)
        this->topics = (char**)realloc(this->topics, topics_lengthT * sizeof(char*));
      offset += 3;
      topics_length = topics_lengthT;
      for( uint8_t i = 0; i < topics_length; i++){
      uint32_t length_st_topics;
      memcpy(&length_st_topics, (inbuffer + offset), sizeof(uint32_t));
      offset += 4;
      for(unsigned int k= offset; k< offset+length_st_topics; ++k){
          inbuffer[k-1]=inbuffer[k];
      }
      inbuffer[offset+length_st_topics-1]=0;
      this->st_topics = (char *)(inbuffer + offset-1);
      offset += length_st_topics;
        memcpy( &(this->topics[i]), &(this->st_topics), sizeof(char*));
      }
     return offset;
    }

    const char * getType(){ return "rosgraph_msgs/Log"; };
    const char * getMD5(){ return "acffd30cd6b6de30f120938c17c593fb"; };

  };

}
#endif