Colony » Colony Scout

/**

 * Copyright (c) 2011 Colony Project

 * 

 * Permission is hereby granted, free of charge, to any person

 * obtaining a copy of this software and associated documentation

 * files (the "Software"), to deal in the Software without

 * restriction, including without limitation the rights to use,

 * copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following

 * conditions:

 * 

 * The above copyright notice and this permission notice shall be

 * included in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

 * OTHER DEALINGS IN THE SOFTWARE.

 **/

/**

 * @file usbserial.cpp

 * @brief USBSerial

 *

 * Implementation of functions for USB/Serial use.

 *

 * @author Colony Project, CMU Robotics Club

 * @author Lalitha Ganesan

 **/

#include "ros/ros.h"

#include "usbserial.h"

#include <cstdlib>

/**

 * @defgroup usbserial USBSerial

 * @brief Functions for using the USB/Serial Ports

 *

 **/

/* USB/Serial state variables */

int data; /**< The USB serial data received. */

int num_data_bits; /**< The number of bits that store data. */

int num_stop_bits; /**< The number of bits that indicate the end of data. */

int parity_type; /**< The parity type of the data being sent over. */

int baud_rate; /**< The baud rate of the USB/Serial (bits/sec). */

/*!

 * \brief USBSerial driver. This is a ROS node that controls USB/Serial 

  * port data.

 *

 * This is the main function for the usbserial node. It is run when the node

 * starts and initializes USB/Serial ports. It then subscribes to the

 * send_serial_data topic, and publishes to the receive_serial_data message.

 * 

 * \param argc The number of command line arguments (should be 1)

 * \param argv The array of command line arguments

 **/

int main(int argc, char **argv){

  /* Initialize in ROS the usbserial driver node */

  ros::init(argc, argv, "usbserial_driver");

  /* Subscribe to the send_serial_data topic */

  ros::Subscriber sub0 = n.subscribe("send_serial_data", send_serial_data);

  /* Publish to the receive_serial_data topic */

  ros::Publisher pub0 = n.publish("receive_serial_data", receive_serial_data);

  /* Initialize hardware for USB/Serial ports */

  // Hardware init functions here

  ROS_INFO("Ready to set USB/Serial.");

  ros::spin();

  return 0;

}

/*!

 * \brief Sends USB/Serial data.

 *

 * Sets the state vars based on subscription to the send_serial_data topic.

 *

 * \param msg The message from the send_serial_data topic, containing info about 

 * how data are being sent.

 */

void send_serial_data(const usbserial::send_serial_data::ConstPtr& msg){

  data = msg->data;

  num_data_bits = msg->num_data_bits;

  num_stop_bits = msg->num_stop_bits;

  parity_type = msg->parity_type;

  baud_rate = msg->baud_rate;

}

/*!

 * \brief Handles received USB/Serial data.

 *

 * Serves the service receive_serial_data by responding to service requests with the

 * usb/serial data.

 * \param req The request. Should be empty.

 * \param res The response. The fields will be filled with values.

 */

bool receive_serial_data(usbserial::receive_serial_data::Request &req,

    usbserial::receive_serial_data::Response &res){

  res.data = data;

  res.num_data_bits = num_data_bits;

  res.num_stop_bits = num_stop_bits;

  res.parity_type = parity_type;

  res.baud_rate = baud_rate;

  return true;

}