/***************************************************************************
*                                                                          *
*         Laser Range finder Functions:  lrf_functions.h                   *
*                                                                          *
* Function Proto-types and constant definitions.                           *
*                                                                          *
* WRITTEN BY:  Bill Kapralos                                               *
* DATE:        June 9, 1997                                                *
*                                                                          *
* York University                                                          *
* Department of Computer Science                                           *
*                                                                          *
*    The serial port initialization code (serialPortInit), was  obtained   *
* from the Greg Reid's Lego project (York University), and  from  tty-io.c *
* written by James R. Service. The function fdHasCharacters() was also     *
* obtained from code written by James R. Service (lrfd.c).                 *
*                                                                          *
****************************************************************************/

#ifndef LRF_FUNCTIONS
#define LRF_FUNCTIONS

   #include <unistd.h>
   #include <ctype.h>
   #include <stdio.h>
   #include <errno.h>
   #include <sys/termios.h>
   #include <fcntl.h>
   #include <time.h>
   #include <sys/filio.h>

   /* laser Range Finder control commands. */

   #define LR_TIMEOUT       "150\r"  /* Shots per reading. */  
   #define BEEPON           "B\r"
   #define BEEPOFF          "Q\r"
   #define INMETERES        "M\r"
   #define INFEET           "F\r"
   #define SINGLEUPDATE     "S\r"
   #define CONT_UPDATE      "C\r"
   #define SATURATEDREADING '('
   #define BATTERYLOW       '*'
   #define LR_READINGLEN    11       /* 8 bytes data + "\r\n" + '\0" */
 
   #define LRF_READY_STRING  "READY" /* Sent by LRF once it is turned ON and
                                        has passed it self-test routine.  */
   #define ERROR             0
   #define CR                '\r'
   #define DECIMAL_POINT     '.' 
   #define ASCII_ZERO '0'
   #define TTY_DEVICE "/dev/ttyb"    /* Serial Port used. */
   #define DELAY_TIME 900            /* Required between commands sent to LRF.*/

   /*****************************************************/

   static int serialFd = 0;     /* Port file descriptor. */
   static int lrfInitialized = 0; 

   /*****************************************************/

   /* Initialize the serial port */
   int serialPortInit(char *);          

   /* Send data to the serial port. */
   int sendCommand(char *, int);

   /* Returns the number of bytes available to be read from the serial port. */
   int fdHasCharacters(int);

   /* Read the data available at the serial port. */
   int getReading(unsigned char *);

   /* Convert number in the string format to a double. */
   float processReading(unsigned char *);

   /* Sends initialization commands to the LRF. */
   void lrfSetUp();

   /* Calculates the avearge value from an array of values. */
   double calcAvgDistance(double *, int);

   /* Display message and exit program. */
   void error(char *);
   
   int lrfChangeShotsPerReading(int);


#endif