File content as of revision 5:e674692f6d15:

#include "mbed.h"
#include "QEI.h"
#include "ros.h"
#include "geometry_msgs/Quaternion.h"
#include <tf/transform_broadcaster.h>
#include <nav_msgs/Odometry.h>

//PINA / PINB / INDEXPIN / PPR / ENCODING (X2 BY DEFAULT)
QEI leftX(D4, D5, NC, 378,QEI::X2_ENCODING);
QEI leftY(D10, D11, NC, 378,QEI::X2_ENCODING);
QEI rightX(D0, D1, NC, 378,QEI::X2_ENCODING);
QEI rightY(D2, D3, NC, 378,QEI::X2_ENCODING);

ros::NodeHandle nh;
geometry_msgs::Quaternion wheelMsg;


geometry_msgs::Quaternion odom_quat;
geometry_msgs::TransformStamped odom_trans;
tf::TransformBroadcaster odom_broadcaster;
ros::Publisher wheelPub("/odom_msg", &wheelMsg); 

//rosserial does not like volatile ints
int leftPosX=0; 
int leftPosY=0;
int rightPosX=0; 
int rightPosY=0;

double theta=0;
ros::Time current_time;

int main(){
    nh.initNode();
    odom_broadcaster.init(nh);
    //nh.advertise(chatter);
    nh.advertise(wheelPub);
    //nh.advertise(odom_quat);
    // pc.baud(57600);
    

    while(true){
    
    current_time = nh.now();
    
    leftPosX = leftX.getPulses();
    leftPosY = leftY.getPulses();
    rightPosX = rightX.getPulses();
    rightPosY = rightY.getPulses();
    
    wheelMsg.x= leftPosX;
    wheelMsg.y = leftPosY;
    wheelMsg.z = rightPosX;
    wheelMsg.w = rightPosY;    
    
    odom_quat.x=0;
    odom_quat.y=0;
    odom_quat.z=0;
    odom_quat.w=0;    
 
    
    odom_trans.header.stamp= current_time;
    odom_trans.header.frame_id="world";
    odom_trans.header.stamp = current_time;
    odom_trans.child_frame_id = "base_link";
    odom_trans.transform.translation.x = rightPosX;
    odom_trans.transform.translation.y = rightPosY;
    odom_trans.transform.translation.z = 0.0;
    odom_trans.transform.rotation = odom_quat;    
 
    //send the transform
    odom_broadcaster.sendTransform(odom_trans);
    
    wheelPub.publish(&wheelMsg);
    nh.spinOnce();
    wait(1000);
    }
}