777 lines
21 KiB
C
777 lines
21 KiB
C
/*
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* Copyright (c) 2007, Swedish Institute of Computer Science.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the Institute nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* This file is part of the Contiki operating system.
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*
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* $Id: xmac.c,v 1.28 2009/03/12 21:58:20 adamdunkels Exp $
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*/
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/**
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* \file
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* A simple power saving MAC protocol based on X-MAC [SenSys 2006]
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* \author
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* Adam Dunkels <adam@sics.se>
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*/
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#include "sys/pt.h"
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#include "net/mac/xmac.h"
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#include "sys/rtimer.h"
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#include "dev/leds.h"
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#include "net/rime.h"
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#include "net/rime/timesynch.h"
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#include "dev/radio.h"
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#include "dev/watchdog.h"
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#include "lib/random.h"
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#include "sys/compower.h"
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#include "sys/timetable.h"
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#include "contiki-conf.h"
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#include <string.h>
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#if CHAMELEON
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#include "net/chameleon/packattr.h"
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#endif
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#define WITH_TIMETABLE 0
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#define WITH_CHANNEL_CHECK 0 /* Seems to work badly when enabled */
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#define WITH_TIMESYNCH 0
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#define WITH_QUEUE 0
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#define WITH_ACK_OPTIMIZATION 1
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struct announcement_data {
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uint16_t id;
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uint16_t value;
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};
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/* The maximum number of announcements in a single announcement
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message - may need to be increased in the future. */
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#define ANNOUNCEMENT_MAX 10
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/* The length of the header of the announcement message, i.e., the
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"num" field in the struct. */
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#define ANNOUNCEMENT_MSG_HEADERLEN 2
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/* The structure of the announcement messages. */
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struct announcement_msg {
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uint16_t num;
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struct announcement_data data[ANNOUNCEMENT_MAX];
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};
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#define TYPE_STROBE 0
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#define TYPE_DATA 1
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#define TYPE_ANNOUNCEMENT 2
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struct xmac_hdr {
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uint16_t type;
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rimeaddr_t sender;
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rimeaddr_t receiver;
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};
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#ifdef XMAC_CONF_ON_TIME
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#define DEFAULT_ON_TIME (XMAC_CONF_ON_TIME)
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#else
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#define DEFAULT_ON_TIME (RTIMER_ARCH_SECOND / 200)
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#endif
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#ifdef XMAC_CONF_OFF_TIME
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#define DEFAULT_OFF_TIME (XMAC_CONF_OFF_TIME)
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#else
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#define DEFAULT_OFF_TIME (RTIMER_ARCH_SECOND / 2 - DEFAULT_ON_TIME)
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#endif
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/* The cycle time for announcements. */
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#define ANNOUNCEMENT_PERIOD 4 * CLOCK_SECOND
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/* The time before sending an announcement within one announcement
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cycle. */
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#define ANNOUNCEMENT_TIME (random_rand() % (ANNOUNCEMENT_PERIOD))
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#define DEFAULT_STROBE_WAIT_TIME (7 * DEFAULT_ON_TIME / 8)
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struct xmac_config xmac_config = {
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DEFAULT_ON_TIME,
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DEFAULT_OFF_TIME,
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20 * DEFAULT_ON_TIME + DEFAULT_OFF_TIME,
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DEFAULT_STROBE_WAIT_TIME
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};
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#include <stdio.h>
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static struct rtimer rt;
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static struct pt pt;
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static int xmac_is_on = 0;
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static volatile unsigned char waiting_for_packet = 0;
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static volatile unsigned char someone_is_sending = 0;
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static volatile unsigned char we_are_sending = 0;
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static volatile unsigned char radio_is_on = 0;
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static const struct radio_driver *radio;
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#undef LEDS_ON
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#undef LEDS_OFF
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#undef LEDS_TOGGLE
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#define CPRINTF(...)
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#define LEDS_ON(x) leds_on(x)
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#define LEDS_OFF(x) leds_off(x)
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#define LEDS_TOGGLE(x) leds_toggle(x)
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#define DEBUG 0
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#if DEBUG
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#include <stdio.h>
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#define PRINTF(...) printf(__VA_ARGS__)
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#else
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#undef LEDS_ON
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#undef LEDS_OFF
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#undef LEDS_TOGGLE
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#define LEDS_ON(x)
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#define LEDS_OFF(x)
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#define LEDS_TOGGLE(x)
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#define PRINTF(...)
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#endif
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#if XMAC_CONF_ANNOUNCEMENTS
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/* Timers for keeping track of when to send announcements. */
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static struct ctimer announcement_cycle_ctimer, announcement_ctimer;
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#endif /* XMAC_CONF_ANNOUNCEMENTS */
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/* Flag that is used to keep track of whether or not we are listening
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for announcements from neighbors. */
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static uint8_t is_listening;
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static void (* receiver_callback)(const struct mac_driver *);
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#if XMAC_CONF_COMPOWER
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static struct compower_activity current_packet;
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#endif /* XMAC_CONF_COMPOWER */
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#if WITH_TIMETABLE
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#define xmac_timetable_size 1024
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TIMETABLE_NONSTATIC(xmac_timetable);
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#endif /* WITH_TIMETABLE */
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/*---------------------------------------------------------------------------*/
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static void
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set_receive_function(void (* recv)(const struct mac_driver *))
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{
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receiver_callback = recv;
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}
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/*---------------------------------------------------------------------------*/
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static void
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on(void)
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{
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if(xmac_is_on && radio_is_on == 0) {
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radio_is_on = 1;
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radio->on();
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LEDS_ON(LEDS_RED);
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CPRINTF("/");
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "on");
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#endif
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}
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}
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/*---------------------------------------------------------------------------*/
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static void
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off(void)
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{
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if(xmac_is_on && radio_is_on != 0 && is_listening == 0) {
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radio_is_on = 0;
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radio->off();
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "off");
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#endif
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LEDS_OFF(LEDS_RED);
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CPRINTF("\\");
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}
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}
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/*---------------------------------------------------------------------------*/
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static char
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powercycle(struct rtimer *t, void *ptr)
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{
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int r;
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#if WITH_TIMESYNCH
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rtimer_clock_t should_be, adjust;
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#endif /* WITH_TIMESYNCH */
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CPRINTF("*");
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PT_BEGIN(&pt);
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while(1) {
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/* Only wait for some cycles to pass for someone to start sending */
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if(someone_is_sending > 0) {
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someone_is_sending--;
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}
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if(xmac_config.off_time > 0) {
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if(waiting_for_packet == 0) {
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if(we_are_sending == 0) {
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off();
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#if XMAC_CONF_COMPOWER
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compower_accumulate(&compower_idle_activity);
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#endif /* XMAC_CONF_COMPOWER */
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}
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} else {
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waiting_for_packet++;
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if(waiting_for_packet > 2) {
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/* We should not be awake for more than two consecutive
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power cycles without having heard a packet, so we turn off
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the radio. */
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waiting_for_packet = 0;
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "off waiting");
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#endif
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off();
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#if XMAC_CONF_COMPOWER
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compower_accumulate(&compower_idle_activity);
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#endif /* XMAC_CONF_COMPOWER */
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}
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}
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#if WITH_TIMESYNCH
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#define NUM_SLOTS 8
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should_be = ((timesynch_rtimer_to_time(RTIMER_TIME(t)) +
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xmac_config.off_time) &
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~(xmac_config.off_time + xmac_config.on_time - 1)) +
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(rimeaddr_node_addr.u8[0] % NUM_SLOTS *
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((xmac_config.off_time + xmac_config.on_time) / NUM_SLOTS));
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should_be = timesynch_time_to_rtimer(should_be);
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if(should_be - RTIMER_TIME(t) > xmac_config.off_time) {
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adjust = xmac_config.off_time / 2;
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} else {
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adjust = should_be - RTIMER_TIME(t);
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}
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r = rtimer_set(t, RTIMER_TIME(t) + adjust, 1,
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(void (*)(struct rtimer *, void *))powercycle, ptr);
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#else /* WITH_TIMESYNCH */
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r = rtimer_set(t, RTIMER_TIME(t) + xmac_config.off_time, 1,
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(void (*)(struct rtimer *, void *))powercycle, ptr);
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#endif /* WITH_TIMESYNCH */
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if(r) {
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PRINTF("xmac: 1 could not set rtimer %d\n", r);
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}
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PT_YIELD(&pt);
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}
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if(we_are_sending == 0 &&
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waiting_for_packet == 0) {
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on();
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}
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r = rtimer_set(t, RTIMER_TIME(t) + xmac_config.on_time, 1,
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(void (*)(struct rtimer *, void *))powercycle, ptr);
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if(r) {
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PRINTF("xmac: 3 could not set rtimer %d\n", r);
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}
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PT_YIELD(&pt);
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}
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PT_END(&pt);
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}
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/*---------------------------------------------------------------------------*/
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#if XMAC_CONF_ANNOUNCEMENTS
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static int
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parse_announcements(rimeaddr_t *from)
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{
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/* Parse incoming announcements */
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struct announcement_msg *adata = packetbuf_dataptr();
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int i;
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PRINTF("%d.%d: probe from %d.%d with %d announcements\n",
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rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
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hdr->sender.u8[0], hdr->sender.u8[1], adata->num);
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for(i = 0; i < adata->num; ++i) {
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PRINTF("%d.%d: announcement %d: %d\n",
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rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
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adata->data[i].id,
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adata->data[i].value);
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announcement_heard(from,
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adata->data[i].id,
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adata->data[i].value);
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}
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return i;
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}
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/*---------------------------------------------------------------------------*/
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static int
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format_announcement(char *hdr)
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{
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struct announcement_msg *adata;
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struct announcement *a;
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/* Construct the announcements */
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adata = (struct announcement_msg *)hdr;
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adata->num = 0;
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for(a = announcement_list();
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a != NULL && adata->num < ANNOUNCEMENT_MAX;
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a = a->next) {
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adata->data[adata->num].id = a->id;
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adata->data[adata->num].value = a->value;
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adata->num++;
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}
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return ANNOUNCEMENT_MSG_HEADERLEN +
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sizeof(struct announcement_data) * adata->num;
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}
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#endif /* XMAC_CONF_ANNOUNCEMENTS */
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/*---------------------------------------------------------------------------*/
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static int
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send_packet(void)
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{
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rtimer_clock_t t0;
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rtimer_clock_t t;
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int strobes;
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struct xmac_hdr hdr;
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int got_strobe_ack = 0;
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struct {
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struct xmac_hdr hdr;
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struct announcement_msg announcement;
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} strobe;
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int len;
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int is_broadcast = 0;
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send");
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#endif
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#if WITH_CHANNEL_CHECK
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/* Check if there are other strobes in the air. */
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waiting_for_packet = 1;
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on();
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t0 = RTIMER_NOW();
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while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + xmac_config.strobe_wait_time * 2)) {
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len = radio->read(&strobe.hdr, sizeof(strobe.hdr));
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if(len > 0) {
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someone_is_sending = 1;
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}
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}
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waiting_for_packet = 0;
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while(someone_is_sending); /* {printf("z");}*/
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send 2");
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#endif /* WITH_TIMETABLE */
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#endif /* WITH_CHANNEL_CHECK */
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/* By setting we_are_sending to one, we ensure that the rtimer
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powercycle interrupt do not interfere with us sending the packet. */
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we_are_sending = 1;
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off();
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/* Create the X-MAC header for the data packet. We cannot do this
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in-place in the packet buffer, because we cannot be sure of the
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alignment of the header in the packet buffer. */
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hdr.type = TYPE_DATA;
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rimeaddr_copy(&hdr.sender, &rimeaddr_node_addr);
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rimeaddr_copy(&hdr.receiver, packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
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if(rimeaddr_cmp(&hdr.receiver, &rimeaddr_null)) {
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is_broadcast = 1;
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}
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/* Copy the X-MAC header to the header portion of the packet
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buffer. */
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packetbuf_hdralloc(sizeof(struct xmac_hdr));
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memcpy(packetbuf_hdrptr(), &hdr, sizeof(struct xmac_hdr));
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packetbuf_compact();
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t0 = RTIMER_NOW();
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strobes = 0;
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LEDS_ON(LEDS_BLUE);
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/* Send a train of strobes until the receiver answers with an ACK. */
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/* Turn on the radio to listen for the strobe ACK. */
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if(!is_broadcast) {
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on();
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}
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watchdog_stop();
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got_strobe_ack = 0;
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for(strobes = 0;
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got_strobe_ack == 0 &&
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RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + xmac_config.strobe_time);
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strobes++) {
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t = RTIMER_NOW();
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strobe.hdr.type = TYPE_STROBE;
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rimeaddr_copy(&strobe.hdr.sender, &rimeaddr_node_addr);
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rimeaddr_copy(&strobe.hdr.receiver, packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
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#if WITH_TIMETABLE
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if(rimeaddr_cmp(&strobe.hdr.receiver, &rimeaddr_null)) {
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TIMETABLE_TIMESTAMP(xmac_timetable, "send broadcast strobe");
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} else {
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TIMETABLE_TIMESTAMP(xmac_timetable, "send strobe");
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}
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#endif
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/* Send the strobe packet. */
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radio->send((const uint8_t *)&strobe, sizeof(struct xmac_hdr));
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CPRINTF("+");
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while(got_strobe_ack == 0 &&
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RTIMER_CLOCK_LT(RTIMER_NOW(), t + xmac_config.strobe_wait_time)) {
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/* See if we got an ACK */
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len = radio->read((uint8_t *)&strobe, sizeof(struct xmac_hdr));
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if(len > 0) {
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CPRINTF("_");
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if(rimeaddr_cmp(&strobe.hdr.sender, &rimeaddr_node_addr) &&
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rimeaddr_cmp(&strobe.hdr.receiver, &rimeaddr_node_addr)) {
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send ack received");
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#endif
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CPRINTF("@");
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/* We got an ACK from the receiver, so we can immediately send
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the packet. */
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got_strobe_ack = 1;
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}
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}
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}
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/* XXX: turn off radio if we haven't heard an ACK within a
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specified time interval. */
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/* if(got_strobe_ack == 0) {
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off();
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while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + xmac_config.strobe_wait_time));
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on();
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}*/
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}
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/* If we have received the strobe ACK, and we are sending a packet
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that will need an upper layer ACK (as signified by the
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PACKETBUF_ATTR_RELIABLE packet attribute), we keep the radio on. */
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if(got_strobe_ack && packetbuf_attr(PACKETBUF_ATTR_RELIABLE)) {
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send got ack");
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#endif
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#if WITH_ACK_OPTIMIZATION
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on(); /* Wait for ACK packet */
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waiting_for_packet = 1;
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#else /* WITH_ACK_OPTIMIZATION */
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off();
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#endif /* WITH_ACK_OPTIMIZATION */
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} else {
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send no ack received");
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#endif
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off(); /* shell ping don't seem to work with off() here, so we'll
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keep it on() for a while. */
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}
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/* Send the data packet. */
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if(is_broadcast || got_strobe_ack) {
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#if WITH_TIMETABLE
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TIMETABLE_TIMESTAMP(xmac_timetable, "send packet");
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#endif
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radio->send(packetbuf_hdrptr(), packetbuf_totlen());
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CPRINTF("#");
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}
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watchdog_start();
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PRINTF("xmac: send (strobes=%u,len=%u,%s), done\n", strobes,
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packetbuf_totlen(), got_strobe_ack ? "ack" : "no ack");
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#if XMAC_CONF_COMPOWER
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/* Accumulate the power consumption for the packet transmission. */
|
|
compower_accumulate(¤t_packet);
|
|
|
|
/* Convert the accumulated power consumption for the transmitted
|
|
packet to packet attributes so that the higher levels can keep
|
|
track of the amount of energy spent on transmitting the
|
|
packet. */
|
|
compower_attrconv(¤t_packet);
|
|
|
|
/* Clear the accumulated power consumption so that it is ready for
|
|
the next packet. */
|
|
compower_clear(¤t_packet);
|
|
#endif /* XMAC_CONF_COMPOWER */
|
|
|
|
we_are_sending = 0;
|
|
#if WITH_TIMETABLE
|
|
TIMETABLE_TIMESTAMP(xmac_timetable, "send we_are_sending = 0");
|
|
#endif
|
|
LEDS_OFF(LEDS_BLUE);
|
|
return 1;
|
|
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static struct queuebuf *queued_packet;
|
|
static int
|
|
qsend_packet(void)
|
|
{
|
|
if(someone_is_sending) {
|
|
PRINTF("xmac: should queue packet, now just dropping %d %d %d %d.\n",
|
|
waiting_for_packet, someone_is_sending, we_are_sending, radio_is_on);
|
|
if(queued_packet != NULL) {
|
|
RIMESTATS_ADD(sendingdrop);
|
|
return 0;
|
|
} else {
|
|
#if WITH_QUEUE
|
|
queued_packet = queuebuf_new_from_packetbuf();
|
|
return 1;
|
|
#else
|
|
RIMESTATS_ADD(sendingdrop);
|
|
return 0;
|
|
#endif
|
|
}
|
|
} else {
|
|
PRINTF("xmac: send immediately.\n");
|
|
return send_packet();
|
|
}
|
|
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static void
|
|
input_packet(const struct radio_driver *d)
|
|
{
|
|
if(receiver_callback) {
|
|
receiver_callback(&xmac_driver);
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static int
|
|
read_packet(void)
|
|
{
|
|
struct xmac_hdr *hdr;
|
|
uint8_t len;
|
|
|
|
packetbuf_clear();
|
|
|
|
len = radio->read(packetbuf_dataptr(), PACKETBUF_SIZE);
|
|
|
|
if(len > 0) {
|
|
packetbuf_set_datalen(len);
|
|
hdr = packetbuf_dataptr();
|
|
|
|
packetbuf_hdrreduce(sizeof(struct xmac_hdr));
|
|
|
|
if(hdr->type == TYPE_STROBE) {
|
|
CPRINTF(".");
|
|
/* There is no data in the packet so it has to be a strobe. */
|
|
someone_is_sending = 2;
|
|
|
|
if(rimeaddr_cmp(&hdr->receiver, &rimeaddr_node_addr)) {
|
|
/* This is a strobe packet for us. */
|
|
|
|
if(rimeaddr_cmp(&hdr->sender, &rimeaddr_node_addr)) {
|
|
/* If the sender address is our node address, the strobe is
|
|
a stray strobe ACK to us, which we ignore unless we are
|
|
currently sending a packet. */
|
|
CPRINTF("&");
|
|
someone_is_sending = 0;
|
|
} else {
|
|
struct xmac_hdr msg;
|
|
/* If the sender address is someone else, we should
|
|
acknowledge the strobe and wait for the packet. By using
|
|
the same address as both sender and receiver, we flag the
|
|
message is a strobe ack. */
|
|
#if WITH_TIMETABLE
|
|
TIMETABLE_TIMESTAMP(xmac_timetable, "read send ack");
|
|
#endif
|
|
rimeaddr_copy(&msg.receiver, &hdr->sender);
|
|
rimeaddr_copy(&msg.sender, &hdr->sender);
|
|
CPRINTF("!");
|
|
/* We turn on the radio in anticipation of the incoming
|
|
packet. */
|
|
someone_is_sending = 1;
|
|
waiting_for_packet = 1;
|
|
on();
|
|
radio->send((const uint8_t *)&msg, sizeof(struct xmac_hdr));
|
|
}
|
|
} else if(rimeaddr_cmp(&hdr->receiver, &rimeaddr_null)) {
|
|
/* If the receiver address is null, the strobe is sent to
|
|
prepare for an incoming broadcast packet. If this is the
|
|
case, we turn on the radio and wait for the incoming
|
|
broadcast packet. */
|
|
waiting_for_packet = 1;
|
|
on();
|
|
}
|
|
|
|
/* Check for annoucements in the strobe */
|
|
/* if(packetbuf_datalen() > 0) {
|
|
parse_announcements(&hdr->sender);
|
|
}*/
|
|
/* We are done processing the strobe and we therefore return
|
|
to the caller. */
|
|
return RIME_OK;
|
|
} else if(hdr->type == TYPE_DATA) {
|
|
CPRINTF("-");
|
|
someone_is_sending = 0;
|
|
if(rimeaddr_cmp(&hdr->receiver, &rimeaddr_node_addr) ||
|
|
rimeaddr_cmp(&hdr->receiver, &rimeaddr_null)) {
|
|
#if WITH_TIMETABLE
|
|
TIMETABLE_TIMESTAMP(xmac_timetable, "read got packet");
|
|
#endif
|
|
/* This is a regular packet that is destined to us or to the
|
|
broadcast address. */
|
|
|
|
/* We have received the final packet, so we can go back to being
|
|
asleep. */
|
|
off();
|
|
|
|
#if XMAC_CONF_COMPOWER
|
|
/* Accumulate the power consumption for the packet reception. */
|
|
compower_accumulate(¤t_packet);
|
|
/* Convert the accumulated power consumption for the received
|
|
packet to packet attributes so that the higher levels can
|
|
keep track of the amount of energy spent on receiving the
|
|
packet. */
|
|
compower_attrconv(¤t_packet);
|
|
|
|
/* Clear the accumulated power consumption so that it is ready
|
|
for the next packet. */
|
|
compower_clear(¤t_packet);
|
|
#endif /* XMAC_CONF_COMPOWER */
|
|
|
|
waiting_for_packet = 0;
|
|
|
|
/* XXX should set timer to send queued packet later. */
|
|
if(queued_packet != NULL) {
|
|
queuebuf_free(queued_packet);
|
|
queued_packet = NULL;
|
|
}
|
|
|
|
return packetbuf_totlen();
|
|
}
|
|
#if XMAC_CONF_ANNOUNCEMENTS
|
|
} else if(hdr->type == TYPE_ANNOUNCEMENT) {
|
|
parse_announcements(&hdr->sender);
|
|
#endif /* XMAC_CONF_ANNOUNCEMENTS */
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
#if XMAC_CONF_ANNOUNCEMENTS
|
|
static void
|
|
send_announcement(void *ptr)
|
|
{
|
|
struct xmac_hdr *hdr;
|
|
int announcement_len;
|
|
|
|
/* Set up the probe header. */
|
|
packetbuf_clear();
|
|
packetbuf_set_datalen(sizeof(struct xmac_hdr));
|
|
hdr = packetbuf_dataptr();
|
|
hdr->type = TYPE_ANNOUNCEMENT;
|
|
rimeaddr_copy(&hdr->sender, &rimeaddr_node_addr);
|
|
rimeaddr_copy(&hdr->receiver, &rimeaddr_null);
|
|
|
|
announcement_len = format_announcement((char *)hdr +
|
|
sizeof(struct xmac_hdr));
|
|
|
|
packetbuf_set_datalen(sizeof(struct xmac_hdr) + announcement_len);
|
|
|
|
/* PRINTF("Sending probe\n");*/
|
|
radio->send(packetbuf_hdrptr(), packetbuf_totlen());
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static void
|
|
cycle_announcement(void *ptr)
|
|
{
|
|
ctimer_set(&announcement_ctimer, ANNOUNCEMENT_TIME,
|
|
send_announcement, NULL);
|
|
ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_PERIOD,
|
|
cycle_announcement, NULL);
|
|
if(is_listening > 0) {
|
|
is_listening--;
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static void
|
|
listen_callback(int periods)
|
|
{
|
|
is_listening = periods + 1;
|
|
}
|
|
#endif /* XMAC_CONF_ANNOUNCEMENTS */
|
|
/*---------------------------------------------------------------------------*/
|
|
const struct mac_driver *
|
|
xmac_init(const struct radio_driver *d)
|
|
{
|
|
#if WITH_TIMETABLE
|
|
timetable_clear(&xmac_timetable);
|
|
#endif
|
|
radio_is_on = 0;
|
|
waiting_for_packet = 0;
|
|
PT_INIT(&pt);
|
|
rtimer_set(&rt, RTIMER_NOW() + xmac_config.off_time, 1,
|
|
(void (*)(struct rtimer *, void *))powercycle, NULL);
|
|
|
|
xmac_is_on = 1;
|
|
radio = d;
|
|
radio->set_receive_function(input_packet);
|
|
|
|
#if XMAC_CONF_ANNOUNCEMENTS
|
|
announcement_register_listen_callback(listen_callback);
|
|
ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_TIME,
|
|
cycle_announcement, NULL);
|
|
#endif /* XMAC_CONF_ANNOUNCEMENTS */
|
|
return &xmac_driver;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static int
|
|
turn_on(void)
|
|
{
|
|
xmac_is_on = 1;
|
|
return 1;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static int
|
|
turn_off(int keep_radio_on)
|
|
{
|
|
xmac_is_on = 0;
|
|
if(keep_radio_on) {
|
|
return radio->on();
|
|
} else {
|
|
return radio->off();
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
const struct mac_driver xmac_driver =
|
|
{
|
|
"X-MAC",
|
|
qsend_packet,
|
|
read_packet,
|
|
set_receive_function,
|
|
turn_on,
|
|
turn_off
|
|
};
|