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/**
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* Copyright (c) 2007 Colony Project
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*
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* Permission is hereby granted, free of charge, to any person
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* obtaining a copy of this software and associated documentation
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* files (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use,
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* copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following
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* conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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* OTHER DEALINGS IN THE SOFTWARE.
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**/
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/**
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* @file xbee.c
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* @brief XBee Interface
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*
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* Implementation of low level communication with the XBee in API mode.
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*
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* @author Brian Coltin, Colony Project, CMU Robotics Club
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**/
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#include "xbee.h" |
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#include "wl_defs.h" |
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#ifndef ROBOT
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#include <fcntl.h> |
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#include <unistd.h> |
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#include <pthread.h> |
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#include <errno.h> |
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#include <termios.h> |
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#else
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#include <serial.h> |
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#include <avr/interrupt.h> |
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#endif
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#define XBEE_FRAME_START 0x7E |
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/*Frame Types*/
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#define XBEE_FRAME_STATUS 0x8A |
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#define XBEE_FRAME_AT_COMMAND 0x08 |
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#define XBEE_FRAME_AT_COMMAND_RESPONSE 0x88 |
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#define XBEE_FRAME_TX_REQUEST_64 0x00 |
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#define XBEE_FRAME_TX_REQUEST_16 0x01 |
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#define XBEE_FRAME_TX_STATUS XBEE_TX_STATUS
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#define XBEE_FRAME_RX_64 0x80 |
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#define XBEE_FRAME_RX_16 XBEE_RX
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/*Internal Function Prototypes*/
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/*I/O Functions*/
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static int xbee_send(char* buf, int size); |
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static int xbee_send_string(char* c); |
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#ifndef ROBOT
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static int xbee_read(char* buf, int size); |
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#endif
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/*Command Mode Functions
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* Called during initialization.
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*/
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static int xbee_enter_command_mode(void); |
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static int xbee_exit_command_mode(void); |
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static int xbee_enter_api_mode(void); |
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static int xbee_exit_api_mode(void); |
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static void xbee_wait_for_string(char* s, int len); |
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static void xbee_wait_for_ok(void); |
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/*API Mode Functions*/
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static int xbee_handle_packet(char* packet, int len); |
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static void xbee_handle_at_command_response(char* command, char result, char* extra, int extraLen); |
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static void xbee_handle_status(char status); |
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static int xbee_verify_checksum(char* packet, int len); |
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static char xbee_compute_checksum(char* packet, int len); |
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static int xbee_send_frame(char* buf, int len); |
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static int xbee_send_read_at_command(char* command); |
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static int xbee_send_modify_at_command(char* command, char* value); |
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/*Global Variables*/
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#ifndef ROBOT
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static char* xbee_com_port = XBEE_PORT_DEFAULT; |
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static int xbee_stream; |
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static pthread_t* xbee_listen_thread;
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#endif
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// TODO: is this a good size?
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#define XBEE_BUFFER_SIZE 256 |
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// a buffer for data received from the XBee
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char arrival_buf[XBEE_BUFFER_SIZE];
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// location of last unread byte in buffer
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volatile int buffer_last = 0; |
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// first unread byte in buffer
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volatile int buffer_first = 0; |
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//used to store packets as they are read
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static char xbee_buf[128]; |
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static int currentBufPos = 0; |
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//XBee status
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static unsigned int xbee_panID = XBEE_PAN_DEFAULT; |
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static unsigned int xbee_pending_panID = XBEE_PAN_DEFAULT; |
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static int xbee_channel = XBEE_CHANNEL_DEFAULT; |
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static int xbee_pending_channel = XBEE_CHANNEL_DEFAULT; |
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static unsigned int xbee_address = 0; |
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/*Function Implementations*/
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#ifdef ROBOT
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/**
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* Interrupt for the robot. Adds bytes received from the xbee
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* to the buffer.
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**/
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#ifndef FIREFLY
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ISR(USART1_RX_vect) |
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{ |
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char c = UDR1;
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arrival_buf[buffer_last] = c; |
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int t = buffer_last + 1; |
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if (t == XBEE_BUFFER_SIZE)
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t = 0;
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if (t == buffer_first)
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{ |
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WL_DEBUG_PRINT("Out of space in buffer.\n");
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} |
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buffer_last = t; |
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} |
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#else
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SIGNAL(SIG_USART0_RECV) |
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{ |
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char c = UDR0;
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arrival_buf[buffer_last] = c; |
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int t = buffer_last + 1; |
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if (t == XBEE_BUFFER_SIZE)
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t = 0;
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if (t == buffer_first)
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{ |
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WL_DEBUG_PRINT("Out of space in buffer.\n");
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} |
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buffer_last = t; |
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} |
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#endif
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#else
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// Computer code
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/**
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* Thread that listens to the xbee.
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**/
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static void* listen_to_xbee(void* x) |
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{ |
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char c;
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while (1) |
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{ |
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if (xbee_read(&c, 1) != 0) { |
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fprintf(stderr, "xbee_read failed.\n");
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return NULL; |
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} |
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arrival_buf[buffer_last] = c; |
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int t = buffer_last + 1; |
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if (t == XBEE_BUFFER_SIZE)
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t = 0;
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if (t == buffer_first)
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{ |
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WL_DEBUG_PRINT("Out of space in buffer.\n");
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} |
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buffer_last = t; |
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usleep(1000);
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} |
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return NULL; |
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} |
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#endif
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/**
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* Initializes the XBee library so that other functions may be used.
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**/
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int xbee_lib_init()
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{ |
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arrival_buf[0] = 'A'; |
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arrival_buf[1] = 'A'; |
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arrival_buf[2] = 'A'; |
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#ifdef ROBOT
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//enable the receiving interrupt
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#ifdef FIREFLY
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UCSR0B |= _BV(RXCIE) | _BV(RXEN); |
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#else
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UCSR1B |= _BV(RXCIE); |
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#endif
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sei(); |
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#else
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printf("Connecting to port %s.\n", xbee_com_port);
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xbee_stream = open(xbee_com_port, O_RDWR); |
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if (xbee_stream == -1/* || lockf(xbee_stream, F_TEST, 0) != 0*/) |
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{ |
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printf("Failed to open connection to XBee on port %s\r\n", xbee_com_port);
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return -1; |
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} |
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// set baud rate, etc. correctly
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struct termios options;
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tcgetattr(xbee_stream, &options); |
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cfsetispeed(&options, B9600); |
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cfsetospeed(&options, B9600); |
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options.c_iflag &= ~ICRNL; |
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options.c_oflag &= ~OCRNL; |
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options.c_cflag |= (CLOCAL | CREAD); |
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options.c_cflag &= ~PARENB; |
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options.c_cflag &= ~CSTOPB; |
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options.c_cflag &= ~CSIZE; |
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options.c_cflag |= CS8; |
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options.c_lflag &= ~ICANON; |
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options.c_cc[VMIN] = 1;
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options.c_cc[VTIME] = 50;
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if (tcsetattr(xbee_stream, TCSANOW, &options))
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{ |
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fprintf(stderr, "Error setting attributes.\n");
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return -1; |
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} |
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//lockf(xbee_stream, F_LOCK, 0);
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xbee_listen_thread = (pthread_t*)malloc(sizeof(pthread_t));
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if (xbee_listen_thread == NULL) |
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{ |
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fprintf(stderr, "%s: Malloc failed.\n", __FUNCTION__);
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return -1; |
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} |
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int ret = pthread_create(xbee_listen_thread, NULL, listen_to_xbee, NULL); |
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if (ret)
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{ |
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fprintf(stderr, "Failed to create listener thread.\r\n");
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return -1; |
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} |
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#endif
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if (xbee_enter_command_mode() != 0) { |
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return -1; |
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} |
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if (xbee_enter_api_mode() != 0) { |
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return -1; |
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} |
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if (xbee_exit_command_mode() != 0) { |
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return -1; |
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} |
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if (xbee_send_read_at_command("MY")) { |
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return -1; |
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} |
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//wait to return until the address is set
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while (xbee_address == 0) xbee_get_packet(NULL); |
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return 0; |
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} |
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/**
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* Call when finished using the XBee library. This releases
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* all sued resources.
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**/
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void xbee_terminate()
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{ |
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#ifndef ROBOT
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pthread_cancel(*xbee_listen_thread); |
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free(xbee_listen_thread); |
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lockf(xbee_stream, F_ULOCK, 0);
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close(xbee_stream); |
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#endif
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} |
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/**
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* Send a buffer buf of size bytes to the XBee.
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*
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* @param buf the buffer of data to send
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* @param size the number of bytes to send
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**/
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static int xbee_send(char* buf, int size) |
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{ |
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#ifdef ROBOT
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int i;
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for (i = 0; i < size; i++) { |
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xbee_putc(buf[i]); |
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} |
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return 0; |
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#else
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int ret = write(xbee_stream, buf, size);
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//success
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if (ret == size)
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return 0; |
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if (ret == -1) |
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{ |
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//interrupted by system signal, probably timer interrupt.
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//just try again
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if (errno == 4) |
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{ |
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return xbee_send(buf, size);
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} |
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printf("Failed to write to xbee, error %i.\r\n", errno);
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return -1; |
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} |
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//write was interrupted after writing ret bytes
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return xbee_send(buf + ret, size - ret);
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#endif
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} |
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/**
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* Sends a string to the XBee.
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*
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* @param c the string to send to the XBEE
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**/
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static int xbee_send_string(char* c) |
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{ |
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return xbee_send(c, strlen(c));
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} |
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#ifndef ROBOT
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static int xbee_read(char* buf, int size) |
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{ |
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if (read(xbee_stream, buf, size) == -1) { |
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printf("Failed to read from xbee.\r\n");
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return -1; |
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} |
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return 0; |
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} |
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#endif
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/**
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* Enter into command mode.
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**/
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static int xbee_enter_command_mode() |
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{ |
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if (xbee_send_string("+++") != 0) { |
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return -1; |
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} |
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xbee_wait_for_ok(); |
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return 0; |
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} |
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/**
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* Exit from command mode.
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**/
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static int xbee_exit_command_mode() |
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{ |
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if (xbee_send_string("ATCN\r") != 0) { |
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return -1; |
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} |
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xbee_wait_for_ok(); |
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return 0; |
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} |
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/**
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* Enter API mode.
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**/
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static int xbee_enter_api_mode() |
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{ |
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if (xbee_send_string("ATAP 1\r") != 0) { |
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return -1; |
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} |
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xbee_wait_for_ok(); |
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return 0; |
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} |
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/**
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* Exit API mode. (warning - does not check for response)
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**/
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static int xbee_exit_api_mode() |
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{ |
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return xbee_send_string("ATAP 0\r"); |
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} |
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/**
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* Wait until the string "OK\r" is received from the XBee.
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**/
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static void xbee_wait_for_ok() |
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{ |
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xbee_wait_for_string("OK\r", 3); |
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} |
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/**
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* Delay until the specified string is received from
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* the XBee. Discards all other XBee data.
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*
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* @param s the string to receive
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* @param len the length of the string
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**/
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static void xbee_wait_for_string(char* s, int len) |
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{ |
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char* curr = s;
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while (curr - s < len) {
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// check if buffer is empty
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if (buffer_last != buffer_first) {
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char c = arrival_buf[buffer_first++];
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if (buffer_first == XBEE_BUFFER_SIZE) {
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buffer_first = 0;
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} |
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if (c == *curr) {
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curr++; |
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} else {
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curr = s; |
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} |
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} |
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#ifndef ROBOT
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usleep(1000);
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#endif
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} |
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} |
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/**
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* Verifies that the packets checksum is correct.
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* (If the checksum is correct, the sum of the bytes
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* is 0xFF.)
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*
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* @param packet the packet received. This includes the first
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* three bytes, which are header information from the XBee.
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*
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* @param len The length of the packet received from the XBee
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*
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* @return 0 if the checksum is incorrect, nonzero
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* otherwise
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**/
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int xbee_verify_checksum(char* packet, int len) |
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{ |
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unsigned char sum = 0; |
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int i;
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for (i = 3; i < len; i++) |
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sum += (unsigned char)packet[i]; |
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return sum == 0xFF; |
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} |
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/**
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* Returns the checksum of the given packet.
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*
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* @param buf the data for the packet to send
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* @param len the length of the packet in bytes
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*
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* @return the checksum of the packet, which will
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* become the last byte sent in the packet
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**/
|
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char xbee_compute_checksum(char* buf, int len) |
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{ |
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int i;
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unsigned char sum = 0; |
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for (i = 0; i < len; i++) |
489 |
sum += (unsigned char)buf[i]; |
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return 0xFF - sum; |
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} |
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/**
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* Adds header information and checksum to the given
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* packet and sends it. Header information includes
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* XBEE_FRAME_START and the packet length, as two bytes.
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*
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* @param buf the packet data
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* @param len the size in bytes of the packet data
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*
|
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**/
|
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static int xbee_send_frame(char* buf, int len) |
503 |
{ |
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char prefix[3]; |
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prefix[0] = XBEE_FRAME_START;
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prefix[1] = (len & 0xFF00) >> 8; |
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prefix[2] = len & 0xFF; |
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char checksum = xbee_compute_checksum(buf, len);
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if (xbee_send(prefix, 3) != 0) { |
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return -1; |
512 |
} |
513 |
|
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if (xbee_send(buf, len) != 0) { |
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return -1; |
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} |
517 |
|
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if (xbee_send(&checksum, 1) != 0) { |
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return -1; |
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} |
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return 0; |
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} |
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|
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/**
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* Sends an AT command to read a parameter.
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*
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* @param command the AT command to send. For exmaple,
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* use ID to read the PAN ID and MY to return the XBee ID.
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* See the XBee reference guide for a complete listing.
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**/
|
532 |
static int xbee_send_read_at_command(char* command) |
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{ |
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return xbee_send_modify_at_command(command, NULL); |
535 |
} |
536 |
|
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/**
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538 |
* Sends the given AT command.
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539 |
*
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* @param command the AT command to send (e.g., MY, ID)
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541 |
* @param value the value to pass as a parameter
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* (or NULL if there is no parameter)
|
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**/
|
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static int xbee_send_modify_at_command(char* command, char* value) |
545 |
{ |
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char buf[16]; |
547 |
int i;
|
548 |
|
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buf[0] = XBEE_FRAME_AT_COMMAND;
|
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buf[1] = 1; |
551 |
buf[2] = command[0]; |
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buf[3] = command[1]; |
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int valueLen = 0; |
554 |
if (value != NULL) |
555 |
{ |
556 |
valueLen = strlen(value); |
557 |
if (valueLen > 8) |
558 |
{ |
559 |
WL_DEBUG_PRINT("AT Command too large.\r\n");
|
560 |
return -1; |
561 |
} |
562 |
|
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for (i = 0; i < valueLen; i++) { |
564 |
buf[4 + i] = value[i];
|
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} |
566 |
} |
567 |
|
568 |
return xbee_send_frame(buf, 4 + valueLen); |
569 |
} |
570 |
|
571 |
/**
|
572 |
* Send the specified packet.
|
573 |
*
|
574 |
* @param packet the packet data to send
|
575 |
* @param len the number of bytes in the packet
|
576 |
*
|
577 |
* @param dest the ID of the XBee to send the packet to,
|
578 |
* or XBEE_BROADCAST to send the message to all robots
|
579 |
* in the PAN.
|
580 |
*
|
581 |
* @param options a combination of the flags
|
582 |
* XBEE_OPTIONS_NONE, XBEE_OPTIONS_DISABLE_RESPONSE and
|
583 |
* XBEE_OPTIONS_BROADCAST_ALL_PANS
|
584 |
*
|
585 |
* @param frame the frame number to associate this packet
|
586 |
* with. This will be used to identify the response when
|
587 |
* the XBee alerts us as to whether or not our message
|
588 |
* was received.
|
589 |
**/
|
590 |
int xbee_send_packet(char* packet, int len, int dest, char options, char frame) |
591 |
{ |
592 |
char buf[5]; |
593 |
char prefix[3]; |
594 |
int i;
|
595 |
unsigned char checksum = 0; |
596 |
|
597 |
if (len > 100) |
598 |
{ |
599 |
WL_DEBUG_PRINT("Packet is too large.\r\n");
|
600 |
return -1; |
601 |
} |
602 |
|
603 |
//data for sending request
|
604 |
buf[0] = XBEE_FRAME_TX_REQUEST_16;
|
605 |
buf[1] = frame;
|
606 |
buf[2] = (dest >> 8) & 0xFF; |
607 |
buf[3] = dest & 0xFF; |
608 |
buf[4] = options;
|
609 |
|
610 |
//packet prefix, do this here so we don't need an extra buffer
|
611 |
prefix[0] = XBEE_FRAME_START;
|
612 |
prefix[1] = ((5 + len) & 0xFF00) >> 8; |
613 |
prefix[2] = (5 + len) & 0xFF; |
614 |
|
615 |
for (i = 0; i < 5; i++) |
616 |
checksum += (unsigned char)buf[i]; |
617 |
for (i = 0; i < len; i++) |
618 |
checksum += (unsigned char)packet[i]; |
619 |
checksum = 0xFF - checksum;
|
620 |
|
621 |
if (xbee_send(prefix, 3) != 0) { |
622 |
return -1; |
623 |
} |
624 |
|
625 |
if (xbee_send(buf, 5) != 0) { |
626 |
return -1; |
627 |
} |
628 |
|
629 |
if (xbee_send(packet, len) != 0) { |
630 |
return -1; |
631 |
} |
632 |
|
633 |
if (xbee_send((char*)&checksum, 1) != 0) { |
634 |
return -1; |
635 |
} |
636 |
|
637 |
return 0; |
638 |
} |
639 |
|
640 |
/**
|
641 |
* Reads a packet received from the XBee. This function
|
642 |
* is non-blocking. The resulting packet is stored in dest.
|
643 |
* Only returns transmission response packets and
|
644 |
* received packets. The returned packet does not include
|
645 |
* header information or the checksum. This method also
|
646 |
* handles special packets dealt with by the XBee library,
|
647 |
* and so should be called frequently while the XBee is in
|
648 |
* use.<br><br>
|
649 |
*
|
650 |
* The first byte of the packet will be either
|
651 |
* XBEE_TX_STATUS or XBEE_RX to indicated
|
652 |
* a response to a sent message or a received message,
|
653 |
* respectively.<br><br>
|
654 |
*
|
655 |
* For a status response packet:<br>
|
656 |
* The first byte will be XBEE_TX_STATUS.<br>
|
657 |
* The second byte will be the frame number.<br>
|
658 |
* The third byte will be the result. 0 indicates success,
|
659 |
* and nonzero indicates that an error ocurred in
|
660 |
* transmitting the packet.<br><br>
|
661 |
*
|
662 |
* For a received packet:<br>
|
663 |
* The first byte will be XBEE_RX.<br>
|
664 |
* The second and third bytes will be the 16-bit
|
665 |
* address of the packet's sender.<br>
|
666 |
* The fourth byte is the signal strength.<br>
|
667 |
* The fifth byte is 1 if the packet were sent to
|
668 |
* a specific address, and 2 if it is a broadcast packet.<br><br>
|
669 |
*
|
670 |
* @param dest set to the packet data
|
671 |
* @return the length of the packet, or -1 if no packet
|
672 |
* is available
|
673 |
**/
|
674 |
int xbee_get_packet(unsigned char* dest) |
675 |
{ |
676 |
//start reading a packet with XBEE_FRAME_START
|
677 |
if (currentBufPos == 0) |
678 |
{ |
679 |
do
|
680 |
{ |
681 |
if (buffer_first == XBEE_BUFFER_SIZE)
|
682 |
buffer_first = 0;
|
683 |
// check if buffer is empty
|
684 |
if (buffer_first == buffer_last)
|
685 |
return -1; |
686 |
} while (arrival_buf[buffer_first++] != XBEE_FRAME_START);
|
687 |
|
688 |
if (buffer_first == XBEE_BUFFER_SIZE) {
|
689 |
buffer_first = 0;
|
690 |
} |
691 |
xbee_buf[0] = XBEE_FRAME_START;
|
692 |
currentBufPos++; |
693 |
} |
694 |
|
695 |
int len = -1; |
696 |
if (currentBufPos >= 3) { |
697 |
len = (int)xbee_buf[2] + ((int)xbee_buf[1] << 8); |
698 |
} |
699 |
|
700 |
while (len == -1 //packet length has not been read yet |
701 |
|| currentBufPos < len + 4)
|
702 |
{ |
703 |
if (currentBufPos == 3) |
704 |
{ |
705 |
len = (int)xbee_buf[2] + ((int)xbee_buf[1] << 8); |
706 |
if (len > 120) |
707 |
{ |
708 |
WL_DEBUG_PRINT("Packet too large. Probably error in XBee transmission.\n");
|
709 |
currentBufPos = 0;
|
710 |
return -1; |
711 |
} |
712 |
} |
713 |
|
714 |
// check if buffer is empty
|
715 |
if (buffer_first == buffer_last) {
|
716 |
return -1; |
717 |
} |
718 |
xbee_buf[currentBufPos++] = arrival_buf[buffer_first++]; |
719 |
if (buffer_first == XBEE_BUFFER_SIZE) {
|
720 |
buffer_first = 0;
|
721 |
} |
722 |
} |
723 |
|
724 |
currentBufPos = 0;
|
725 |
|
726 |
if (!xbee_verify_checksum(xbee_buf, len + 4)) |
727 |
{ |
728 |
WL_DEBUG_PRINT("XBee checksum failed.\r\n");
|
729 |
return -1; |
730 |
} |
731 |
|
732 |
//we will take care of the packet
|
733 |
if (xbee_handle_packet(xbee_buf + 3, len)) { |
734 |
return -1; |
735 |
} |
736 |
|
737 |
if (dest == NULL) { |
738 |
return -1; |
739 |
} |
740 |
|
741 |
int i;
|
742 |
for (i = 3; i < len + 3; i++) { |
743 |
dest[i - 3] = xbee_buf[i];
|
744 |
} |
745 |
|
746 |
return len;
|
747 |
} |
748 |
|
749 |
/**
|
750 |
* Handles modem status packets.
|
751 |
*
|
752 |
* @param status the type of status packet received.
|
753 |
**/
|
754 |
void xbee_handle_status(char status) |
755 |
{ |
756 |
switch (status)
|
757 |
{ |
758 |
case 0: |
759 |
WL_DEBUG_PRINT("XBee hardware reset.\r\n");
|
760 |
break;
|
761 |
case 1: |
762 |
WL_DEBUG_PRINT("Watchdog timer reset.\r\n");
|
763 |
break;
|
764 |
case 2: |
765 |
WL_DEBUG_PRINT("Associated.\r\n");
|
766 |
break;
|
767 |
case 3: |
768 |
WL_DEBUG_PRINT("Disassociated.\r\n");
|
769 |
break;
|
770 |
case 4: |
771 |
WL_DEBUG_PRINT("Synchronization lost.\r\n");
|
772 |
break;
|
773 |
case 5: |
774 |
WL_DEBUG_PRINT("Coordinator realignment.\r\n");
|
775 |
break;
|
776 |
case 6: |
777 |
WL_DEBUG_PRINT("Coordinator started.\r\n");
|
778 |
break;
|
779 |
} |
780 |
} |
781 |
|
782 |
/**
|
783 |
* Handles AT command response packets.
|
784 |
* @param command the two character AT command, e.g. MY or ID
|
785 |
* @param result 0 for success, 1 for an error
|
786 |
* @param extra the hex value of the requested register
|
787 |
* @param extraLen the length in bytes of extra
|
788 |
**/
|
789 |
static void xbee_handle_at_command_response(char* command, char result, char* extra, int extraLen) |
790 |
{ |
791 |
if (result == 1) |
792 |
{ |
793 |
WL_DEBUG_PRINT("Error with AT");
|
794 |
WL_DEBUG_PRINT(command); |
795 |
WL_DEBUG_PRINT(" packet.\r\n");
|
796 |
} |
797 |
WL_DEBUG_PRINT("AT");
|
798 |
WL_DEBUG_PRINT(command); |
799 |
WL_DEBUG_PRINT(" command was successful.\r\n");
|
800 |
|
801 |
if (command[0] == 'I' && command[1] == 'D') |
802 |
{ |
803 |
xbee_panID = xbee_pending_panID; |
804 |
WL_DEBUG_PRINT("PAN ID set to ");
|
805 |
WL_DEBUG_PRINT_INT(xbee_panID); |
806 |
WL_DEBUG_PRINT(".\r\n");
|
807 |
return;
|
808 |
} |
809 |
|
810 |
if (command[0] == 'C' && command[1] == 'H') |
811 |
{ |
812 |
xbee_channel = xbee_pending_channel; |
813 |
WL_DEBUG_PRINT("Channel set to ");
|
814 |
WL_DEBUG_PRINT_INT(xbee_channel); |
815 |
WL_DEBUG_PRINT(".\r\n");
|
816 |
return;
|
817 |
} |
818 |
|
819 |
if (command[0] == 'M' && command[1] == 'Y' && extraLen != 0) |
820 |
{ |
821 |
// printf("reading xbee_address\n");
|
822 |
|
823 |
xbee_address = 0;
|
824 |
int i;
|
825 |
for (i = 0; i < extraLen; i++) { |
826 |
xbee_address = (xbee_address << 8) + extra[i];
|
827 |
} |
828 |
// printf("xbee address is: %d\n", xbee_address);
|
829 |
|
830 |
WL_DEBUG_PRINT("XBee address is ");
|
831 |
WL_DEBUG_PRINT_INT(xbee_address); |
832 |
WL_DEBUG_PRINT(".\r\n");
|
833 |
|
834 |
if (xbee_address == 0) |
835 |
{ |
836 |
WL_DEBUG_PRINT("XBee 16-bit address must be set using ATMY.\r\n");
|
837 |
exit(0);
|
838 |
} |
839 |
} |
840 |
} |
841 |
|
842 |
/**
|
843 |
* Attempts to handle the packet if it is dealt with
|
844 |
* by the library.
|
845 |
* We will handle the following packet types:
|
846 |
* Modem Status
|
847 |
* AT Command Response
|
848 |
*
|
849 |
* @param packet the packet to handle
|
850 |
* @param len the length of the packet
|
851 |
*
|
852 |
* @return 1 if we have handled the packet, 0 otherwise
|
853 |
*/
|
854 |
static int xbee_handle_packet(char* packet, int len) |
855 |
{ |
856 |
char command[3] = {1, 2, 3}; |
857 |
if (len <= 0) //this should not happend |
858 |
{ |
859 |
WL_DEBUG_PRINT("Non-positive packet length.\r\n");
|
860 |
return 0; |
861 |
} |
862 |
|
863 |
switch ((unsigned char)packet[0]) //packet type |
864 |
{ |
865 |
case XBEE_FRAME_STATUS:
|
866 |
xbee_handle_status(packet[1]);
|
867 |
return 1; |
868 |
case XBEE_FRAME_AT_COMMAND_RESPONSE:
|
869 |
command[0] = packet[2]; |
870 |
command[1] = packet[3]; |
871 |
command[2] = 0; |
872 |
xbee_handle_at_command_response(command, packet[4], packet + 5, len - 5); |
873 |
return 1; |
874 |
} |
875 |
return 0; |
876 |
} |
877 |
|
878 |
/**
|
879 |
* Sets the personal area network id.
|
880 |
*
|
881 |
* @param id the new personal area network (PAN) id
|
882 |
**/
|
883 |
int xbee_set_pan_id(int id) |
884 |
{ |
885 |
char s[3]; |
886 |
s[0] = (id >> 8) & 0xFF; |
887 |
s[1] = id & 0xFF; |
888 |
s[2] = 0; |
889 |
xbee_pending_panID = id; |
890 |
return xbee_send_modify_at_command("ID", s); |
891 |
} |
892 |
|
893 |
/**
|
894 |
* Get the PAN ID for the XBee.
|
895 |
*
|
896 |
* @return the personal area network id, or
|
897 |
* XBEE_PAN_DEFAULT if it has not yet been set.
|
898 |
**/
|
899 |
unsigned int xbee_get_pan_id() |
900 |
{ |
901 |
return xbee_panID;
|
902 |
} |
903 |
|
904 |
/**
|
905 |
* Set the channel the XBee is using.
|
906 |
*
|
907 |
* @param channel the channel the XBee will not use,
|
908 |
* between 0x0B and 0x1A
|
909 |
*
|
910 |
* @see xbee_get_channel
|
911 |
**/
|
912 |
int xbee_set_channel(int channel) |
913 |
{ |
914 |
if (channel < 0x0B || channel > 0x1A) |
915 |
{ |
916 |
WL_DEBUG_PRINT("Channel out of range.\r\n");
|
917 |
return -1; |
918 |
} |
919 |
|
920 |
char s[3]; |
921 |
s[0] = channel & 0xFF; |
922 |
s[1] = 0; |
923 |
xbee_pending_channel = channel; |
924 |
|
925 |
return xbee_send_modify_at_command("CH", s); |
926 |
} |
927 |
|
928 |
/**
|
929 |
* Returns the channel which the XBee is currently using.
|
930 |
*
|
931 |
* @return the channel the XBee is using
|
932 |
*
|
933 |
* @see xbee_set_channel
|
934 |
**/
|
935 |
int xbee_get_channel(void) |
936 |
{ |
937 |
return xbee_channel;
|
938 |
} |
939 |
|
940 |
/**
|
941 |
* Get the 16-bit address of the XBee.
|
942 |
* This is used to specify who to send messages to
|
943 |
* and who messages are from.
|
944 |
*
|
945 |
* @return the 16-bit address of the XBee.
|
946 |
**/
|
947 |
unsigned int xbee_get_address() |
948 |
{ |
949 |
return xbee_address;
|
950 |
} |
951 |
|
952 |
#ifndef ROBOT
|
953 |
void xbee_set_com_port(char* port) |
954 |
{ |
955 |
xbee_com_port = port; |
956 |
} |
957 |
#endif
|
958 |
|