/* * Copyright (c) 2007, Swedish Institute of Computer Science. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * This file is part of the Contiki operating system. * * $Id: cxmac.c,v 1.15 2010/10/03 20:37:32 adamdunkels Exp $ */ /** * \file * A simple power saving MAC protocol based on X-MAC [SenSys 2006] * \author * Adam Dunkels * Niclas Finne * Joakim Eriksson */ #include "dev/leds.h" #include "dev/radio.h" #include "dev/watchdog.h" #include "net/netstack.h" #include "lib/random.h" #include "net/mac/cxmac.h" #include "net/rime.h" #include "net/rime/timesynch.h" #include "sys/compower.h" #include "sys/pt.h" #include "sys/rtimer.h" #include "contiki-conf.h" #ifdef EXPERIMENT_SETUP #include "experiment-setup.h" #endif #include #ifndef WITH_ACK_OPTIMIZATION #define WITH_ACK_OPTIMIZATION 1 #endif #ifndef WITH_ENCOUNTER_OPTIMIZATION #define WITH_ENCOUNTER_OPTIMIZATION 1 #endif #ifndef WITH_STREAMING #define WITH_STREAMING 1 #endif #ifndef WITH_STROBE_BROADCAST #define WITH_STROBE_BROADCAST 0 #endif struct announcement_data { uint16_t id; uint16_t value; }; /* The maximum number of announcements in a single announcement message - may need to be increased in the future. */ #define ANNOUNCEMENT_MAX 10 /* The structure of the announcement messages. */ struct announcement_msg { uint16_t num; struct announcement_data data[ANNOUNCEMENT_MAX]; }; /* The length of the header of the announcement message, i.e., the "num" field in the struct. */ #define ANNOUNCEMENT_MSG_HEADERLEN (sizeof (uint16_t)) #define DISPATCH 0 #define TYPE_STROBE 0x10 /* #define TYPE_DATA 0x11 */ #define TYPE_ANNOUNCEMENT 0x12 #define TYPE_STROBE_ACK 0x13 struct cxmac_hdr { uint8_t dispatch; uint8_t type; }; #define MAX_STROBE_SIZE 50 #ifdef CXMAC_CONF_ON_TIME #define DEFAULT_ON_TIME (CXMAC_CONF_ON_TIME) #else #define DEFAULT_ON_TIME (RTIMER_ARCH_SECOND / 160) #endif #ifdef CXMAC_CONF_OFF_TIME #define DEFAULT_OFF_TIME (CXMAC_CONF_OFF_TIME) #else #define DEFAULT_OFF_TIME (RTIMER_ARCH_SECOND / NETSTACK_RDC_CHANNEL_CHECK_RATE - DEFAULT_ON_TIME) #endif #define DEFAULT_PERIOD (DEFAULT_OFF_TIME + DEFAULT_ON_TIME) #define WAIT_TIME_BEFORE_STROBE_ACK RTIMER_ARCH_SECOND / 1000 /* On some platforms, we may end up with a DEFAULT_PERIOD that is 0 which will make compilation fail due to a modulo operation in the code. To ensure that DEFAULT_PERIOD is greater than zero, we use the construct below. */ #if DEFAULT_PERIOD == 0 #undef DEFAULT_PERIOD #define DEFAULT_PERIOD 1 #endif /* The cycle time for announcements. */ #define ANNOUNCEMENT_PERIOD 4 * CLOCK_SECOND /* The time before sending an announcement within one announcement cycle. */ #define ANNOUNCEMENT_TIME (random_rand() % (ANNOUNCEMENT_PERIOD)) #define DEFAULT_STROBE_WAIT_TIME (7 * DEFAULT_ON_TIME / 8) struct cxmac_config cxmac_config = { DEFAULT_ON_TIME, DEFAULT_OFF_TIME, 4 * DEFAULT_ON_TIME + DEFAULT_OFF_TIME, DEFAULT_STROBE_WAIT_TIME }; #include static struct pt pt; static volatile uint8_t cxmac_is_on = 0; static volatile unsigned char waiting_for_packet = 0; static volatile unsigned char someone_is_sending = 0; static volatile unsigned char we_are_sending = 0; static volatile unsigned char radio_is_on = 0; #undef LEDS_ON #undef LEDS_OFF #undef LEDS_TOGGLE #define LEDS_ON(x) leds_on(x) #define LEDS_OFF(x) leds_off(x) #define LEDS_TOGGLE(x) leds_toggle(x) #define DEBUG 0 #if DEBUG #include #define PRINTF(...) printf(__VA_ARGS__) #define PRINTDEBUG(...) printf(__VA_ARGS__) #else #undef LEDS_ON #undef LEDS_OFF #undef LEDS_TOGGLE #define LEDS_ON(x) #define LEDS_OFF(x) #define LEDS_TOGGLE(x) #define PRINTF(...) #define PRINTDEBUG(...) #endif #if CXMAC_CONF_ANNOUNCEMENTS /* Timers for keeping track of when to send announcements. */ static struct ctimer announcement_cycle_ctimer, announcement_ctimer; static int announcement_radio_txpower; #endif /* CXMAC_CONF_ANNOUNCEMENTS */ /* Flag that is used to keep track of whether or not we are listening for announcements from neighbors. */ static uint8_t is_listening; #if CXMAC_CONF_COMPOWER static struct compower_activity current_packet; #endif /* CXMAC_CONF_COMPOWER */ #if WITH_ENCOUNTER_OPTIMIZATION #include "lib/list.h" #include "lib/memb.h" struct encounter { struct encounter *next; rimeaddr_t neighbor; rtimer_clock_t time; }; #define MAX_ENCOUNTERS 4 LIST(encounter_list); MEMB(encounter_memb, struct encounter, MAX_ENCOUNTERS); #endif /* WITH_ENCOUNTER_OPTIMIZATION */ static uint8_t is_streaming; static rimeaddr_t is_streaming_to, is_streaming_to_too; static rtimer_clock_t stream_until; #define DEFAULT_STREAM_TIME (RTIMER_ARCH_SECOND) #ifndef MIN #define MIN(a, b) ((a) < (b)? (a) : (b)) #endif /* MIN */ /*---------------------------------------------------------------------------*/ static void on(void) { if(cxmac_is_on && radio_is_on == 0) { radio_is_on = 1; NETSTACK_RADIO.on(); LEDS_ON(LEDS_RED); } } /*---------------------------------------------------------------------------*/ static void off(void) { if(cxmac_is_on && radio_is_on != 0 && is_listening == 0 && is_streaming == 0) { radio_is_on = 0; NETSTACK_RADIO.off(); LEDS_OFF(LEDS_RED); } } /*---------------------------------------------------------------------------*/ static void powercycle_turn_radio_off(void) { if(we_are_sending == 0 && waiting_for_packet == 0) { off(); } #if CXMAC_CONF_COMPOWER compower_accumulate(&compower_idle_activity); #endif /* CXMAC_CONF_COMPOWER */ } static void powercycle_turn_radio_on(void) { if(we_are_sending == 0 && waiting_for_packet == 0) { on(); } } /*---------------------------------------------------------------------------*/ static struct ctimer cpowercycle_ctimer; #define CSCHEDULE_POWERCYCLE(rtime) cschedule_powercycle((1ul * CLOCK_SECOND * (rtime)) / RTIMER_ARCH_SECOND) static char cpowercycle(void *ptr); static void cschedule_powercycle(clock_time_t time) { if(cxmac_is_on) { if(time == 0) { time = 1; } ctimer_set(&cpowercycle_ctimer, time, (void (*)(void *))cpowercycle, NULL); } } /*---------------------------------------------------------------------------*/ static char cpowercycle(void *ptr) { if(is_streaming) { if(!RTIMER_CLOCK_LT(RTIMER_NOW(), stream_until)) { is_streaming = 0; rimeaddr_copy(&is_streaming_to, &rimeaddr_null); rimeaddr_copy(&is_streaming_to_too, &rimeaddr_null); } } PT_BEGIN(&pt); while(1) { /* Only wait for some cycles to pass for someone to start sending */ if(someone_is_sending > 0) { someone_is_sending--; } /* If there were a strobe in the air, turn radio on */ powercycle_turn_radio_on(); CSCHEDULE_POWERCYCLE(DEFAULT_ON_TIME); PT_YIELD(&pt); if(cxmac_config.off_time > 0) { powercycle_turn_radio_off(); if(waiting_for_packet != 0) { waiting_for_packet++; if(waiting_for_packet > 2) { /* We should not be awake for more than two consecutive power cycles without having heard a packet, so we turn off the radio. */ waiting_for_packet = 0; powercycle_turn_radio_off(); } } CSCHEDULE_POWERCYCLE(DEFAULT_OFF_TIME); PT_YIELD(&pt); } } PT_END(&pt); } /*---------------------------------------------------------------------------*/ #if CXMAC_CONF_ANNOUNCEMENTS static int parse_announcements(const rimeaddr_t *from) { /* Parse incoming announcements */ struct announcement_msg adata; int i; memcpy(&adata, packetbuf_dataptr(), MIN(packetbuf_datalen(), sizeof(adata))); /* printf("%d.%d: probe from %d.%d with %d announcements\n", rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1], from->u8[0], from->u8[1], adata->num);*/ /* for(i = 0; i < packetbuf_datalen(); ++i) { printf("%02x ", ((uint8_t *)packetbuf_dataptr())[i]); } printf("\n");*/ for(i = 0; i < adata.num; ++i) { /* printf("%d.%d: announcement %d: %d\n", rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1], adata->data[i].id, adata->data[i].value);*/ announcement_heard(from, adata.data[i].id, adata.data[i].value); } return i; } /*---------------------------------------------------------------------------*/ static int format_announcement(char *hdr) { struct announcement_msg adata; struct announcement *a; /* Construct the announcements */ /* adata = (struct announcement_msg *)hdr;*/ adata.num = 0; for(a = announcement_list(); a != NULL && adata.num < ANNOUNCEMENT_MAX; a = list_item_next(a)) { adata.data[adata.num].id = a->id; adata.data[adata.num].value = a->value; adata.num++; } memcpy(hdr, &adata, sizeof(struct announcement_msg)); if(adata.num > 0) { return ANNOUNCEMENT_MSG_HEADERLEN + sizeof(struct announcement_data) * adata.num; } else { return 0; } } #endif /* CXMAC_CONF_ANNOUNCEMENTS */ /*---------------------------------------------------------------------------*/ #if WITH_ENCOUNTER_OPTIMIZATION static void register_encounter(const rimeaddr_t *neighbor, rtimer_clock_t time) { struct encounter *e; /* If we have an entry for this neighbor already, we renew it. */ for(e = list_head(encounter_list); e != NULL; e = list_item_next(e)) { if(rimeaddr_cmp(neighbor, &e->neighbor)) { e->time = time; break; } } /* No matching encounter was found, so we allocate a new one. */ if(e == NULL) { e = memb_alloc(&encounter_memb); if(e == NULL) { /* We could not allocate memory for this encounter, so we just drop it. */ return; } rimeaddr_copy(&e->neighbor, neighbor); e->time = time; list_add(encounter_list, e); } } #endif /* WITH_ENCOUNTER_OPTIMIZATION */ /*---------------------------------------------------------------------------*/ static int send_packet(void) { rtimer_clock_t t0; rtimer_clock_t t; rtimer_clock_t encounter_time = 0; int strobes; struct cxmac_hdr *hdr; int got_strobe_ack = 0; uint8_t strobe[MAX_STROBE_SIZE]; int strobe_len, len; int is_broadcast = 0; int is_reliable; struct encounter *e; struct queuebuf *packet; int is_already_streaming = 0; uint8_t collisions; /* Create the X-MAC header for the data packet. */ packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr); if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) { is_broadcast = 1; PRINTDEBUG("cxmac: send broadcast\n"); } else { #if UIP_CONF_IPV6 PRINTDEBUG("cxmac: send unicast to %02x%02x:%02x%02x:%02x%02x:%02x%02x\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[1], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[2], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[3], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[4], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[5], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[6], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[7]); #else PRINTDEBUG("cxmac: send unicast to %u.%u\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0], packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[1]); #endif /* UIP_CONF_IPV6 */ } is_reliable = packetbuf_attr(PACKETBUF_ATTR_RELIABLE) || packetbuf_attr(PACKETBUF_ATTR_ERELIABLE); len = NETSTACK_FRAMER.create(); strobe_len = len + sizeof(struct cxmac_hdr); if(len == 0 || strobe_len > (int)sizeof(strobe)) { /* Failed to send */ PRINTF("cxmac: send failed, too large header\n"); return MAC_TX_ERR_FATAL; } memcpy(strobe, packetbuf_hdrptr(), len); strobe[len] = DISPATCH; /* dispatch */ strobe[len + 1] = TYPE_STROBE; /* type */ packetbuf_compact(); packet = queuebuf_new_from_packetbuf(); if(packet == NULL) { /* No buffer available */ PRINTF("cxmac: send failed, no queue buffer available (of %u)\n", QUEUEBUF_CONF_NUM); return MAC_TX_ERR; } #if WITH_STREAMING if(is_streaming == 1 && (rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &is_streaming_to) || rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &is_streaming_to_too))) { is_already_streaming = 1; } if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) == PACKETBUF_ATTR_PACKET_TYPE_STREAM) { is_streaming = 1; if(rimeaddr_cmp(&is_streaming_to, &rimeaddr_null)) { rimeaddr_copy(&is_streaming_to, packetbuf_addr(PACKETBUF_ADDR_RECEIVER)); } else if(!rimeaddr_cmp(&is_streaming_to, packetbuf_addr(PACKETBUF_ADDR_RECEIVER))) { rimeaddr_copy(&is_streaming_to_too, packetbuf_addr(PACKETBUF_ADDR_RECEIVER)); } stream_until = RTIMER_NOW() + DEFAULT_STREAM_TIME; } #endif /* WITH_STREAMING */ off(); #if WITH_ENCOUNTER_OPTIMIZATION /* We go through the list of encounters to find if we have recorded an encounter with this particular neighbor. If so, we can compute the time for the next expected encounter and setup a ctimer to switch on the radio just before the encounter. */ for(e = list_head(encounter_list); e != NULL; e = list_item_next(e)) { const rimeaddr_t *neighbor = packetbuf_addr(PACKETBUF_ADDR_RECEIVER); if(rimeaddr_cmp(neighbor, &e->neighbor)) { rtimer_clock_t wait, now, expected; /* We expect encounters to happen every DEFAULT_PERIOD time units. The next expected encounter is at time e->time + DEFAULT_PERIOD. To compute a relative offset, we subtract with clock_time(). Because we are only interested in turning on the radio within the DEFAULT_PERIOD period, we compute the waiting time with modulo DEFAULT_PERIOD. */ now = RTIMER_NOW(); wait = ((rtimer_clock_t)(e->time - now)) % (DEFAULT_PERIOD); expected = now + wait - 2 * DEFAULT_ON_TIME; #if WITH_ACK_OPTIMIZATION /* Wait until the receiver is expected to be awake */ if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) != PACKETBUF_ATTR_PACKET_TYPE_ACK && is_streaming == 0) { /* Do not wait if we are sending an ACK, because then the receiver will already be awake. */ while(RTIMER_CLOCK_LT(RTIMER_NOW(), expected)); } #else /* WITH_ACK_OPTIMIZATION */ /* Wait until the receiver is expected to be awake */ while(RTIMER_CLOCK_LT(RTIMER_NOW(), expected)); #endif /* WITH_ACK_OPTIMIZATION */ } } #endif /* WITH_ENCOUNTER_OPTIMIZATION */ /* By setting we_are_sending to one, we ensure that the rtimer powercycle interrupt do not interfere with us sending the packet. */ we_are_sending = 1; t0 = RTIMER_NOW(); strobes = 0; LEDS_ON(LEDS_BLUE); /* Send a train of strobes until the receiver answers with an ACK. */ /* Turn on the radio to listen for the strobe ACK. */ on(); collisions = 0; if(!is_already_streaming) { watchdog_stop(); got_strobe_ack = 0; t = RTIMER_NOW(); for(strobes = 0, collisions = 0; got_strobe_ack == 0 && collisions == 0 && RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + cxmac_config.strobe_time); strobes++) { while(got_strobe_ack == 0 && RTIMER_CLOCK_LT(RTIMER_NOW(), t + cxmac_config.strobe_wait_time)) { rtimer_clock_t now = RTIMER_NOW(); /* See if we got an ACK */ packetbuf_clear(); len = NETSTACK_RADIO.read(packetbuf_dataptr(), PACKETBUF_SIZE); if(len > 0) { packetbuf_set_datalen(len); if(NETSTACK_FRAMER.parse()) { hdr = packetbuf_dataptr(); if(hdr->dispatch == DISPATCH && hdr->type == TYPE_STROBE_ACK) { if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_node_addr)) { /* We got an ACK from the receiver, so we can immediately send the packet. */ got_strobe_ack = 1; encounter_time = now; } else { PRINTDEBUG("cxmac: strobe ack for someone else\n"); } } else /*if(hdr->dispatch == DISPATCH && hdr->type == TYPE_STROBE)*/ { PRINTDEBUG("cxmac: strobe from someone else\n"); collisions++; } } else { PRINTF("cxmac: send failed to parse %u\n", len); } } } t = RTIMER_NOW(); /* Send the strobe packet. */ if(got_strobe_ack == 0 && collisions == 0) { if(is_broadcast) { #if WITH_STROBE_BROADCAST NETSTACK_RADIO.send(strobe, strobe_len); #else /* restore the packet to send */ queuebuf_to_packetbuf(packet); NETSTACK_RADIO.send(packetbuf_hdrptr(), packetbuf_totlen()); #endif off(); } else { NETSTACK_RADIO.send(strobe, strobe_len); #if 0 /* Turn off the radio for a while to let the other side respond. We don't need to keep our radio on when we know that the other side needs some time to produce a reply. */ off(); rtimer_clock_t wt = RTIMER_NOW(); while(RTIMER_CLOCK_LT(RTIMER_NOW(), wt + WAIT_TIME_BEFORE_STROBE_ACK)); #endif /* 0 */ on(); } } } } #if WITH_ACK_OPTIMIZATION /* If we have received the strobe ACK, and we are sending a packet that will need an upper layer ACK (as signified by the PACKETBUF_ATTR_RELIABLE packet attribute), we keep the radio on. */ if(got_strobe_ack && (packetbuf_attr(PACKETBUF_ATTR_RELIABLE) || packetbuf_attr(PACKETBUF_ATTR_ERELIABLE) || packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) == PACKETBUF_ATTR_PACKET_TYPE_STREAM)) { on(); /* Wait for ACK packet */ waiting_for_packet = 1; } else { off(); } #else /* WITH_ACK_OPTIMIZATION */ off(); #endif /* WITH_ACK_OPTIMIZATION */ /* restore the packet to send */ queuebuf_to_packetbuf(packet); queuebuf_free(packet); /* Send the data packet. */ if((is_broadcast || got_strobe_ack || is_streaming) && collisions == 0) { NETSTACK_RADIO.send(packetbuf_hdrptr(), packetbuf_totlen()); } #if WITH_ENCOUNTER_OPTIMIZATION if(got_strobe_ack && !is_streaming) { register_encounter(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), encounter_time); } #endif /* WITH_ENCOUNTER_OPTIMIZATION */ watchdog_start(); PRINTF("cxmac: send (strobes=%u,len=%u,%s), done\n", strobes, packetbuf_totlen(), got_strobe_ack ? "ack" : "no ack"); #if CXMAC_CONF_COMPOWER /* 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 /* CXMAC_CONF_COMPOWER */ we_are_sending = 0; LEDS_OFF(LEDS_BLUE); if(collisions == 0) { if(!is_broadcast && !got_strobe_ack) { return MAC_TX_NOACK; } else { return MAC_TX_OK; } } else { someone_is_sending++; return MAC_TX_COLLISION; } } /*---------------------------------------------------------------------------*/ static void qsend_packet(mac_callback_t sent, void *ptr) { int ret; if(someone_is_sending) { PRINTF("cxmac: should queue packet, now just dropping %d %d %d %d.\n", waiting_for_packet, someone_is_sending, we_are_sending, radio_is_on); RIMESTATS_ADD(sendingdrop); ret = MAC_TX_COLLISION; } else { PRINTF("cxmac: send immediately.\n"); ret = send_packet(); } mac_call_sent_callback(sent, ptr, ret, 1); } /*---------------------------------------------------------------------------*/ void qsend_list(mac_callback_t sent, void *ptr, struct rdc_buf_list *buf_list) { if(buf_list != NULL) { queuebuf_to_packetbuf(buf_list->buf); qsend_packet(sent, ptr); } } /*---------------------------------------------------------------------------*/ static void input_packet(void) { struct cxmac_hdr *hdr; if(NETSTACK_FRAMER.parse()) { hdr = packetbuf_dataptr(); if(hdr->dispatch != DISPATCH) { someone_is_sending = 0; if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_node_addr) || rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) { /* 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 CXMAC_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 /* CXMAC_CONF_COMPOWER */ waiting_for_packet = 0; PRINTDEBUG("cxmac: data(%u)\n", packetbuf_datalen()); NETSTACK_MAC.input(); return; } else { PRINTDEBUG("cxmac: data not for us\n"); } } else if(hdr->type == TYPE_STROBE) { someone_is_sending = 2; if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_node_addr)) { /* This is a strobe packet for us. */ /* 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. */ hdr->type = TYPE_STROBE_ACK; packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, packetbuf_addr(PACKETBUF_ADDR_SENDER)); packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr); packetbuf_compact(); if(NETSTACK_FRAMER.create()) { /* We turn on the radio in anticipation of the incoming packet. */ someone_is_sending = 1; waiting_for_packet = 1; on(); NETSTACK_RADIO.send(packetbuf_hdrptr(), packetbuf_totlen()); PRINTDEBUG("cxmac: send strobe ack %u\n", packetbuf_totlen()); } else { PRINTF("cxmac: failed to send strobe ack\n"); } } else if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_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(); } else { PRINTDEBUG("cxmac: strobe not for us\n"); } /* We are done processing the strobe and we therefore return to the caller. */ return; #if CXMAC_CONF_ANNOUNCEMENTS } else if(hdr->type == TYPE_ANNOUNCEMENT) { packetbuf_hdrreduce(sizeof(struct cxmac_hdr)); parse_announcements(packetbuf_addr(PACKETBUF_ADDR_SENDER)); #endif /* CXMAC_CONF_ANNOUNCEMENTS */ } else if(hdr->type == TYPE_STROBE_ACK) { PRINTDEBUG("cxmac: stray strobe ack\n"); } else { PRINTF("cxmac: unknown type %u (%u)\n", hdr->type, packetbuf_datalen()); } } else { PRINTF("cxmac: failed to parse (%u)\n", packetbuf_totlen()); } } /*---------------------------------------------------------------------------*/ #if CXMAC_CONF_ANNOUNCEMENTS static void send_announcement(void *ptr) { struct cxmac_hdr *hdr; int announcement_len; /* Set up the probe header. */ packetbuf_clear(); hdr = packetbuf_dataptr(); announcement_len = format_announcement((char *)hdr + sizeof(struct cxmac_hdr)); if(announcement_len > 0) { packetbuf_set_datalen(sizeof(struct cxmac_hdr) + announcement_len); hdr->dispatch = DISPATCH; hdr->type = TYPE_ANNOUNCEMENT; packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr); packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, &rimeaddr_null); packetbuf_set_attr(PACKETBUF_ATTR_RADIO_TXPOWER, announcement_radio_txpower); if(NETSTACK_FRAMER.create()) { NETSTACK_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--; /* printf("is_listening %d\n", is_listening);*/ } } /*---------------------------------------------------------------------------*/ static void listen_callback(int periods) { is_listening = periods + 1; } #endif /* CXMAC_CONF_ANNOUNCEMENTS */ /*---------------------------------------------------------------------------*/ void cxmac_set_announcement_radio_txpower(int txpower) { #if CXMAC_CONF_ANNOUNCEMENTS announcement_radio_txpower = txpower; #endif /* CXMAC_CONF_ANNOUNCEMENTS */ } /*---------------------------------------------------------------------------*/ void cxmac_init(void) { radio_is_on = 0; waiting_for_packet = 0; PT_INIT(&pt); /* rtimer_set(&rt, RTIMER_NOW() + cxmac_config.off_time, 1, (void (*)(struct rtimer *, void *))powercycle, NULL);*/ cxmac_is_on = 1; #if WITH_ENCOUNTER_OPTIMIZATION list_init(encounter_list); memb_init(&encounter_memb); #endif /* WITH_ENCOUNTER_OPTIMIZATION */ #if CXMAC_CONF_ANNOUNCEMENTS announcement_register_listen_callback(listen_callback); ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_TIME, cycle_announcement, NULL); #endif /* CXMAC_CONF_ANNOUNCEMENTS */ CSCHEDULE_POWERCYCLE(DEFAULT_OFF_TIME); } /*---------------------------------------------------------------------------*/ static int turn_on(void) { cxmac_is_on = 1; /* rtimer_set(&rt, RTIMER_NOW() + cxmac_config.off_time, 1, (void (*)(struct rtimer *, void *))powercycle, NULL);*/ CSCHEDULE_POWERCYCLE(DEFAULT_OFF_TIME); return 1; } /*---------------------------------------------------------------------------*/ static int turn_off(int keep_radio_on) { cxmac_is_on = 0; if(keep_radio_on) { return NETSTACK_RADIO.on(); } else { return NETSTACK_RADIO.off(); } } /*---------------------------------------------------------------------------*/ static unsigned short channel_check_interval(void) { return (1ul * CLOCK_SECOND * DEFAULT_PERIOD) / RTIMER_ARCH_SECOND; } /*---------------------------------------------------------------------------*/ const struct rdc_driver cxmac_driver = { "CX-MAC", cxmac_init, qsend_packet, qsend_list, input_packet, turn_on, turn_off, channel_check_interval, };