/* * Copyright (c) 2010, 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: contikimac.c,v 1.48 2011/01/25 14:29:46 adamdunkels Exp $ */ /** * \file * The Contiki power-saving MAC protocol (ContikiMAC) * \author * Adam Dunkels * Niclas Finne * Joakim Eriksson */ #include "net/netstack.h" #include "dev/leds.h" #include "dev/radio.h" #include "dev/watchdog.h" #include "lib/random.h" #include "net/mac/contikimac.h" #include "net/rime.h" #include "sys/compower.h" #include "sys/pt.h" #include "sys/rtimer.h" /*#include "cooja-debug.h"*/ #include "contiki-conf.h" #ifdef EXPERIMENT_SETUP #include "experiment-setup.h" #endif #include #ifndef WITH_PHASE_OPTIMIZATION #define WITH_PHASE_OPTIMIZATION 1 #endif #ifndef WITH_STREAMING #define WITH_STREAMING 0 #endif #ifndef WITH_CONTIKIMAC_HEADER #define WITH_CONTIKIMAC_HEADER 1 #endif #ifndef WITH_FAST_SLEEP #define WITH_FAST_SLEEP 1 #endif #if NETSTACK_RDC_CHANNEL_CHECK_RATE >= 64 #undef WITH_PHASE_OPTIMIZATION #define WITH_PHASE_OPTIMIZATION 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 #if WITH_CONTIKIMAC_HEADER #define CONTIKIMAC_ID 0x00 struct hdr { uint8_t id; uint8_t len; }; #endif /* WITH_CONTIKIMAC_HEADER */ /* The structure of the announcement messages. */ struct announcement_msg { uint8_t announcement_magic[2]; uint16_t num; struct announcement_data data[ANNOUNCEMENT_MAX]; }; #define ANNOUNCEMENT_MAGIC1 0xAD #define ANNOUNCEMENT_MAGIC2 0xAD /* The length of the header of the announcement message, i.e., the "num" field in the struct. */ #define ANNOUNCEMENT_MSG_HEADERLEN (sizeof(uint16_t) * 2) #ifdef CONTIKIMAC_CONF_CYCLE_TIME #define CYCLE_TIME (CONTIKIMAC_CONF_CYCLE_TIME) #else #define CYCLE_TIME (RTIMER_ARCH_SECOND / NETSTACK_RDC_CHANNEL_CHECK_RATE) #endif /* ContikiMAC performs periodic channel checks. Each channel check consists of two or more CCA checks. CCA_COUNT_MAX is the number of CCAs to be done for each periodic channel check. The default is two.*/ #define CCA_COUNT_MAX 2 /* CCA_CHECK_TIME is the time it takes to perform a CCA check. */ #define CCA_CHECK_TIME RTIMER_ARCH_SECOND / 8192 /* CCA_SLEEP_TIME is the time between two successive CCA checks. */ #define CCA_SLEEP_TIME RTIMER_ARCH_SECOND / 2000 /* CHECK_TIME is the total time it takes to perform CCA_COUNT_MAX CCAs. */ #define CHECK_TIME (CCA_COUNT_MAX * (CCA_CHECK_TIME + CCA_SLEEP_TIME)) /* LISTEN_TIME_AFTER_PACKET_DETECTED is the time that we keep checking for activity after a potential packet has been detected by a CCA check. */ #define LISTEN_TIME_AFTER_PACKET_DETECTED RTIMER_ARCH_SECOND / 80 /* MAX_SILENCE_PERIODS is the maximum amount of periods (a period is CCA_CHECK_TIME + CCA_SLEEP_TIME) that we allow to be silent before we turn of the radio. */ #define MAX_SILENCE_PERIODS 5 /* MAX_NONACTIVITY_PERIODS is the maximum number of periods we allow the radio to be turned on without any packet being received, when WITH_FAST_SLEEP is enabled. */ #define MAX_NONACTIVITY_PERIODS 10 /* STROBE_TIME is the maximum amount of time a transmitted packet should be repeatedly transmitted as part of a transmission. */ #define STROBE_TIME (CYCLE_TIME + 2 * CHECK_TIME) /* GUARD_TIME is the time before the expected phase of a neighbor that a transmitted should begin transmitting packets. */ #define GUARD_TIME 11 * CHECK_TIME /* INTER_PACKET_INTERVAL is the interval between two successive packet transmissions */ #define INTER_PACKET_INTERVAL RTIMER_ARCH_SECOND / 5000 /* AFTER_ACK_DETECTECT_WAIT_TIME is the time to wait after a potential ACK packet has been detected until we can read it out from the radio. */ #define AFTER_ACK_DETECTECT_WAIT_TIME RTIMER_ARCH_SECOND / 1500 /* MAX_PHASE_STROBE_TIME is the time that we transmit repeated packets to a neighbor for which we have a phase lock. */ #define MAX_PHASE_STROBE_TIME RTIMER_ARCH_SECOND / 60 /* SHORTEST_PACKET_SIZE is the shortest packet that ContikiMAC allows. Packets have to be a certain size to be able to be detected by two consecutive CCA checks, and here is where we define this shortest size. */ #define SHORTEST_PACKET_SIZE 43 /* The cycle time for announcements. */ #ifdef ANNOUNCEMENT_CONF_PERIOD #define ANNOUNCEMENT_PERIOD ANNOUNCEMENT_CONF_PERIOD #else /* ANNOUNCEMENT_CONF_PERIOD */ #define ANNOUNCEMENT_PERIOD 1 * CLOCK_SECOND #endif /* ANNOUNCEMENT_CONF_PERIOD */ /* The time before sending an announcement within one announcement cycle. */ #define ANNOUNCEMENT_TIME (random_rand() % (ANNOUNCEMENT_PERIOD)) #define ACK_LEN 3 #include static struct rtimer rt; static struct pt pt; static volatile uint8_t contikimac_is_on = 0; static volatile uint8_t contikimac_keep_radio_on = 0; static volatile unsigned char we_are_sending = 0; static volatile unsigned char radio_is_on = 0; #define DEBUG 0 #if DEBUG #include #define PRINTF(...) printf(__VA_ARGS__) #define PRINTDEBUG(...) printf(__VA_ARGS__) #else #define PRINTF(...) #define PRINTDEBUG(...) #endif #if CONTIKIMAC_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 /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ /* Flag that is used to keep track of whether or not we are snooping for announcements from neighbors. */ static volatile uint8_t is_snooping; #if CONTIKIMAC_CONF_COMPOWER static struct compower_activity current_packet; #endif /* CONTIKIMAC_CONF_COMPOWER */ #if WITH_PHASE_OPTIMIZATION #include "net/mac/phase.h" #ifndef MAX_PHASE_NEIGHBORS #define MAX_PHASE_NEIGHBORS 30 #endif PHASE_LIST(phase_list, MAX_PHASE_NEIGHBORS); #endif /* WITH_PHASE_OPTIMIZATION */ static volatile uint8_t is_streaming; static rimeaddr_t is_streaming_to, is_streaming_to_too; static volatile rtimer_clock_t stream_until; #define DEFAULT_STREAM_TIME (1 * CYCLE_TIME) #ifndef MIN #define MIN(a, b) ((a) < (b)? (a) : (b)) #endif /* MIN */ struct seqno { rimeaddr_t sender; uint8_t seqno; }; #define MAX_SEQNOS 8 static struct seqno received_seqnos[MAX_SEQNOS]; #if CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT static struct timer broadcast_rate_timer; static int broadcast_rate_counter; #endif /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */ /*---------------------------------------------------------------------------*/ static void on(void) { if(contikimac_is_on && radio_is_on == 0) { radio_is_on = 1; NETSTACK_RADIO.on(); } } /*---------------------------------------------------------------------------*/ static void off(void) { if(contikimac_is_on && radio_is_on != 0 && /*is_streaming == 0 &&*/ contikimac_keep_radio_on == 0 /* && is_snooping == 0*/) { radio_is_on = 0; NETSTACK_RADIO.off(); } } /*---------------------------------------------------------------------------*/ static volatile rtimer_clock_t cycle_start; static char powercycle(struct rtimer *t, void *ptr); static void schedule_powercycle(struct rtimer *t, rtimer_clock_t time) { int r; if(contikimac_is_on) { if(RTIMER_CLOCK_LT(RTIMER_TIME(t) + time, RTIMER_NOW() + 2)) { time = RTIMER_NOW() - RTIMER_TIME(t) + 2; } #if NURTIMER r = rtimer_reschedule(t, time, 1); #else r = rtimer_set(t, RTIMER_TIME(t) + time, 1, (void (*)(struct rtimer *, void *))powercycle, NULL); #endif if(r != RTIMER_OK) { printf("schedule_powercycle: could not set rtimer\n"); } } } static void schedule_powercycle_fixed(struct rtimer *t, rtimer_clock_t fixed_time) { int r; if(contikimac_is_on) { if(RTIMER_CLOCK_LT(fixed_time, RTIMER_NOW() + 1)) { fixed_time = RTIMER_NOW() + 1; } #if NURTIMER r = rtimer_reschedule(t, RTIMER_TIME(t) - time, 1); #else r = rtimer_set(t, fixed_time, 1, (void (*)(struct rtimer *, void *))powercycle, NULL); #endif if(r != RTIMER_OK) { printf("schedule_powercycle: could not set rtimer\n"); } } } static void powercycle_turn_radio_off(void) { if(we_are_sending == 0) { off(); } } static void powercycle_turn_radio_on(void) { if(we_are_sending == 0) { on(); } } static char powercycle(struct rtimer *t, void *ptr) { PT_BEGIN(&pt); cycle_start = RTIMER_NOW(); while(1) { static uint8_t packet_seen; static rtimer_clock_t t0; static uint8_t count; cycle_start += CYCLE_TIME; if(WITH_STREAMING && is_streaming) { #if NURTIMER if(!RTIMER_CLOCK_LT(cycle_start, RTIMER_NOW(), stream_until)) #else if(!RTIMER_CLOCK_LT(RTIMER_NOW(), stream_until)) #endif { is_streaming = 0; rimeaddr_copy(&is_streaming_to, &rimeaddr_null); rimeaddr_copy(&is_streaming_to_too, &rimeaddr_null); } } packet_seen = 0; do { for(count = 0; count < CCA_COUNT_MAX; ++count) { t0 = RTIMER_NOW(); if(we_are_sending == 0) { powercycle_turn_radio_on(); // schedule_powercycle_fixed(t, t0 + CCA_CHECK_TIME); #if 0 #if NURTIMER while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_CHECK_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_CHECK_TIME)); #endif #endif /* 0 */ /* Check if a packet is seen in the air. If so, we keep the radio on for a while (LISTEN_TIME_AFTER_PACKET_DETECTED) to be able to receive the packet. We also continuously check the radio medium to make sure that we wasn't woken up by a false positive: a spurious radio interference that was not caused by an incoming packet. */ if(NETSTACK_RADIO.channel_clear() == 0) { packet_seen = 1; break; } powercycle_turn_radio_off(); } // schedule_powercycle_fixed(t, t0 + CCA_CHECK_TIME + CCA_SLEEP_TIME); schedule_powercycle_fixed(t, RTIMER_NOW() + CCA_SLEEP_TIME); /* COOJA_DEBUG_STR("yield\n");*/ PT_YIELD(&pt); } if(packet_seen) { static rtimer_clock_t start; static uint8_t silence_periods, periods; start = RTIMER_NOW(); periods = silence_periods = 0; while(we_are_sending == 0 && radio_is_on && RTIMER_CLOCK_LT(RTIMER_NOW(), (start + LISTEN_TIME_AFTER_PACKET_DETECTED))) { /* Check for a number of consecutive periods of non-activity. If we see two such periods, we turn the radio off. Also, if a packet has been successfully received (as indicated by the NETSTACK_RADIO.pending_packet() function), we stop snooping. */ if(NETSTACK_RADIO.channel_clear()) { ++silence_periods; } else { silence_periods = 0; } ++periods; if(NETSTACK_RADIO.receiving_packet()) { silence_periods = 0; } if(silence_periods > MAX_SILENCE_PERIODS) { powercycle_turn_radio_off(); #if CONTIKIMAC_CONF_COMPOWER compower_accumulate(&compower_idle_activity); #endif /* CONTIKIMAC_CONF_COMPOWER */ break; } if(WITH_FAST_SLEEP && periods > MAX_NONACTIVITY_PERIODS && !(NETSTACK_RADIO.receiving_packet() || NETSTACK_RADIO.pending_packet())) { powercycle_turn_radio_off(); #if CONTIKIMAC_CONF_COMPOWER compower_accumulate(&compower_idle_activity); #endif /* CONTIKIMAC_CONF_COMPOWER */ break; } if(NETSTACK_RADIO.pending_packet()) { break; } schedule_powercycle(t, CCA_CHECK_TIME + CCA_SLEEP_TIME); PT_YIELD(&pt); } if(radio_is_on) { if(!(NETSTACK_RADIO.receiving_packet() || NETSTACK_RADIO.pending_packet()) || !RTIMER_CLOCK_LT(RTIMER_NOW(), (start + LISTEN_TIME_AFTER_PACKET_DETECTED))) { powercycle_turn_radio_off(); #if CONTIKIMAC_CONF_COMPOWER compower_accumulate(&compower_idle_activity); #endif /* CONTIKIMAC_CONF_COMPOWER */ } } } else { #if CONTIKIMAC_CONF_COMPOWER compower_accumulate(&compower_idle_activity); #endif /* CONTIKIMAC_CONF_COMPOWER */ } } while((is_snooping || is_streaming) && RTIMER_CLOCK_LT(RTIMER_NOW() - cycle_start, CYCLE_TIME - CHECK_TIME)); if(RTIMER_CLOCK_LT(RTIMER_NOW() - cycle_start, CYCLE_TIME)) { /* schedule_powercycle(t, CYCLE_TIME - (RTIMER_NOW() - cycle_start));*/ schedule_powercycle_fixed(t, CYCLE_TIME + cycle_start); /* printf("cycle_start 0x%02x now 0x%02x wait 0x%02x\n", cycle_start, RTIMER_NOW(), CYCLE_TIME - (RTIMER_NOW() - cycle_start));*/ PT_YIELD(&pt); } } PT_END(&pt); } /*---------------------------------------------------------------------------*/ #if CONTIKIMAC_CONF_ANNOUNCEMENTS static int parse_announcements(void) { /* Parse incoming announcements */ struct announcement_msg adata; const rimeaddr_t *from; int i; memcpy(&adata, packetbuf_dataptr(), MIN(packetbuf_datalen(), sizeof(adata))); from = packetbuf_addr(PACKETBUF_ADDR_SENDER); /* 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"); */ if(adata.num / sizeof(struct announcement_data) > sizeof(struct announcement_msg)) { /* Sanity check. The number of announcements is too large - corrupt packet has been received. */ return 0; } 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.announcement_magic[0] = ANNOUNCEMENT_MAGIC1; adata.announcement_magic[1] = ANNOUNCEMENT_MAGIC2; adata.num = 0; for(a = announcement_list(); a != NULL && adata.num < ANNOUNCEMENT_MAX; a = a->next) { if(a->has_value) { 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 /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ /*---------------------------------------------------------------------------*/ static int broadcast_rate_drop(void) { #if CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT if(!timer_expired(&broadcast_rate_timer)) { broadcast_rate_counter++; if(broadcast_rate_counter < CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT) { return 0; } else { return 1; } } else { timer_set(&broadcast_rate_timer, CLOCK_SECOND); broadcast_rate_counter = 0; return 0; } #else /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */ return 0; #endif /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */ } /*---------------------------------------------------------------------------*/ static int send_packet(mac_callback_t mac_callback, void *mac_callback_ptr) { rtimer_clock_t t0; rtimer_clock_t encounter_time = 0, previous_txtime = 0; int strobes; uint8_t got_strobe_ack = 0; int hdrlen, len; uint8_t is_broadcast = 0; uint8_t is_reliable = 0; uint8_t is_known_receiver = 0; uint8_t collisions; int transmit_len; int i; int ret; uint8_t contikimac_was_on; #if WITH_CONTIKIMAC_HEADER struct hdr *chdr; #endif /* WITH_CONTIKIMAC_HEADER */ if(packetbuf_totlen() == 0) { PRINTF("contikimac: send_packet data len 0\n"); return MAC_TX_ERR_FATAL; } packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr); if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) { is_broadcast = 1; PRINTDEBUG("contikimac: send broadcast\n"); if(broadcast_rate_drop()) { return MAC_TX_COLLISION; } } else { #if UIP_CONF_IPV6 PRINTDEBUG("contikimac: 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 /* UIP_CONF_IPV6 */ PRINTDEBUG("contikimac: 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); if(WITH_STREAMING) { if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) == PACKETBUF_ATTR_PACKET_TYPE_STREAM) { 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; is_streaming = 1; } else { is_streaming = 0; } } if(is_streaming) { packetbuf_set_attr(PACKETBUF_ATTR_PENDING, 1); } packetbuf_set_attr(PACKETBUF_ATTR_MAC_ACK, 1); if(WITH_CONTIKIMAC_HEADER) { hdrlen = packetbuf_totlen(); if(packetbuf_hdralloc(sizeof(struct hdr)) == 0) { /* Failed to allocate space for contikimac header */ PRINTF("contikimac: send failed, too large header\n"); return MAC_TX_ERR_FATAL; } chdr = packetbuf_hdrptr(); chdr->id = CONTIKIMAC_ID; chdr->len = hdrlen; /* Create the MAC header for the data packet. */ hdrlen = NETSTACK_FRAMER.create(); if(hdrlen == 0) { /* Failed to send */ PRINTF("contikimac: send failed, too large header\n"); packetbuf_hdr_remove(sizeof(struct hdr)); return MAC_TX_ERR_FATAL; } hdrlen += sizeof(struct hdr); } else { /* Create the MAC header for the data packet. */ hdrlen = NETSTACK_FRAMER.create(); if(hdrlen == 0) { /* Failed to send */ PRINTF("contikimac: send failed, too large header\n"); return MAC_TX_ERR_FATAL; } } /* Make sure that the packet is longer or equal to the shortest packet length. */ transmit_len = packetbuf_totlen(); if(transmit_len < SHORTEST_PACKET_SIZE) { #if 0 /* Pad with zeroes */ uint8_t *ptr; ptr = packetbuf_dataptr(); memset(ptr + packetbuf_datalen(), 0, SHORTEST_PACKET_SIZE - packetbuf_totlen()); #endif PRINTF("contikimac: shorter than shortest (%d)\n", packetbuf_totlen()); transmit_len = SHORTEST_PACKET_SIZE; } packetbuf_compact(); NETSTACK_RADIO.prepare(packetbuf_hdrptr(), transmit_len); /* Remove the MAC-layer header since it will be recreated next time around. */ packetbuf_hdr_remove(hdrlen); if(!is_broadcast && !is_streaming) { #if WITH_PHASE_OPTIMIZATION ret = phase_wait(&phase_list, packetbuf_addr(PACKETBUF_ADDR_RECEIVER), CYCLE_TIME, GUARD_TIME, mac_callback, mac_callback_ptr); if(ret == PHASE_DEFERRED) { return MAC_TX_DEFERRED; } if(ret != PHASE_UNKNOWN) { is_known_receiver = 1; } #endif /* WITH_PHASE_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; /* If we have a pending packet in the radio, we should not send now, because we will trash the received packet. Instead, we signal that we have a collision, which lets the packet be received. This packet will be retransmitted later by the MAC protocol instread. */ if(NETSTACK_RADIO.receiving_packet() || NETSTACK_RADIO.pending_packet()) { we_are_sending = 0; PRINTF("contikimac: collision receiving %d, pending %d\n", NETSTACK_RADIO.receiving_packet(), NETSTACK_RADIO.pending_packet()); return MAC_TX_COLLISION; } /* Switch off the radio to ensure that we didn't start sending while the radio was doing a channel check. */ off(); strobes = 0; /* Send a train of strobes until the receiver answers with an ACK. */ collisions = 0; got_strobe_ack = 0; /* Set contikimac_is_on to one to allow the on() and off() functions to control the radio. We restore the old value of contikimac_is_on when we are done. */ contikimac_was_on = contikimac_is_on; contikimac_is_on = 1; if(is_streaming == 0) { /* Check if there are any transmissions by others. */ for(i = 0; i < CCA_COUNT_MAX; ++i) { t0 = RTIMER_NOW(); on(); #if NURTIMER while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_CHECK_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_CHECK_TIME)) { } #endif if(NETSTACK_RADIO.channel_clear() == 0) { collisions++; off(); break; } off(); t0 = RTIMER_NOW(); #if NURTIMER while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_SLEEP_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_SLEEP_TIME)) { } #endif } } if(collisions > 0) { we_are_sending = 0; off(); PRINTF("contikimac: collisions before sending\n"); contikimac_is_on = contikimac_was_on; return MAC_TX_COLLISION; } if(!is_broadcast) { on(); } watchdog_periodic(); t0 = RTIMER_NOW(); #if NURTIMER for(strobes = 0, collisions = 0; got_strobe_ack == 0 && collisions == 0 && RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + STROBE_TIME); strobes++) { #else for(strobes = 0, collisions = 0; got_strobe_ack == 0 && collisions == 0 && RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + STROBE_TIME); strobes++) { #endif watchdog_periodic(); if(is_known_receiver && !RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + MAX_PHASE_STROBE_TIME)) { PRINTF("miss to %d\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0]); break; } len = 0; previous_txtime = RTIMER_NOW(); { rtimer_clock_t wt; rtimer_clock_t txtime; int ret; txtime = RTIMER_NOW(); ret = NETSTACK_RADIO.transmit(transmit_len); wt = RTIMER_NOW(); #if NURTIMER while(RTIMER_CLOCK_LT(wt, RTIMER_NOW(), wt + INTER_PACKET_INTERVAL)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), wt + INTER_PACKET_INTERVAL)) { } #endif if(!is_broadcast && (NETSTACK_RADIO.receiving_packet() || NETSTACK_RADIO.pending_packet() || NETSTACK_RADIO.channel_clear() == 0)) { uint8_t ackbuf[ACK_LEN]; wt = RTIMER_NOW(); #if NURTIMER while(RTIMER_CLOCK_LT(wt, RTIMER_NOW(), wt + AFTER_ACK_DETECTECT_WAIT_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), wt + AFTER_ACK_DETECTECT_WAIT_TIME)) { } #endif len = NETSTACK_RADIO.read(ackbuf, ACK_LEN); if(len == ACK_LEN) { got_strobe_ack = 1; encounter_time = previous_txtime; break; } else { PRINTF("contikimac: collisions while sending\n"); collisions++; } } previous_txtime = txtime; } } off(); PRINTF("contikimac: send (strobes=%u, len=%u, %s, %s), done\n", strobes, packetbuf_totlen(), got_strobe_ack ? "ack" : "no ack", collisions ? "collision" : "no collision"); #if CONTIKIMAC_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 /* CONTIKIMAC_CONF_COMPOWER */ contikimac_is_on = contikimac_was_on; we_are_sending = 0; /* Determine the return value that we will return from the function. We must pass this value to the phase module before we return from the function. */ if(collisions > 0) { ret = MAC_TX_COLLISION; } else if(!is_broadcast && !got_strobe_ack) { ret = MAC_TX_NOACK; } else { ret = MAC_TX_OK; } #if WITH_PHASE_OPTIMIZATION if(is_known_receiver && got_strobe_ack) { PRINTF("no miss %d wake-ups %d\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0], strobes); } if(!is_broadcast) { if(collisions == 0 && is_streaming == 0) { phase_update(&phase_list, packetbuf_addr(PACKETBUF_ADDR_RECEIVER), encounter_time, ret); } } #endif /* WITH_PHASE_OPTIMIZATION */ return ret; } /*---------------------------------------------------------------------------*/ static void qsend_packet(mac_callback_t sent, void *ptr) { int ret = send_packet(sent, ptr); if(ret != MAC_TX_DEFERRED) { // printf("contikimac qsend_packet %p\n", ptr); mac_call_sent_callback(sent, ptr, ret, 1); } } /*---------------------------------------------------------------------------*/ static void input_packet(void) { /* We have received the packet, so we can go back to being asleep. */ off(); /* printf("cycle_start 0x%02x 0x%02x\n", cycle_start, cycle_start % CYCLE_TIME);*/ if(packetbuf_totlen() > 0 && NETSTACK_FRAMER.parse()) { #if WITH_CONTIKIMAC_HEADER struct hdr *chdr; chdr = packetbuf_dataptr(); if(chdr->id != CONTIKIMAC_ID) { PRINTF("contikimac: failed to parse hdr (%u)\n", packetbuf_totlen()); return; } packetbuf_hdrreduce(sizeof(struct hdr)); packetbuf_set_datalen(chdr->len); #endif /* WITH_CONTIKIMAC_HEADER */ if(packetbuf_datalen() > 0 && packetbuf_totlen() > 0 && (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. */ #if CONTIKIMAC_CONF_ANNOUNCEMENTS { struct announcement_msg *hdr = packetbuf_dataptr(); uint8_t magic[2]; memcpy(magic, hdr->announcement_magic, 2); if(magic[0] == ANNOUNCEMENT_MAGIC1 && magic[1] == ANNOUNCEMENT_MAGIC2) { parse_announcements(); } } #endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ #if WITH_PHASE_OPTIMIZATION /* If the sender has set its pending flag, it has its radio turned on and we should drop the phase estimation that we have from before. */ if(packetbuf_attr(PACKETBUF_ATTR_PENDING)) { phase_remove(&phase_list, packetbuf_addr(PACKETBUF_ADDR_SENDER)); } #endif /* WITH_PHASE_OPTIMIZATION */ /* Check for duplicate packet by comparing the sequence number of the incoming packet with the last few ones we saw. */ { int i; for(i = 0; i < MAX_SEQNOS; ++i) { if(packetbuf_attr(PACKETBUF_ATTR_PACKET_ID) == received_seqnos[i].seqno && rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_SENDER), &received_seqnos[i].sender)) { /* Drop the packet. */ /* printf("Drop duplicate ContikiMAC layer packet\n");*/ return; } } for(i = MAX_SEQNOS - 1; i > 0; --i) { memcpy(&received_seqnos[i], &received_seqnos[i - 1], sizeof(struct seqno)); } received_seqnos[0].seqno = packetbuf_attr(PACKETBUF_ATTR_PACKET_ID); rimeaddr_copy(&received_seqnos[0].sender, packetbuf_addr(PACKETBUF_ADDR_SENDER)); } #if CONTIKIMAC_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 /* CONTIKIMAC_CONF_COMPOWER */ PRINTDEBUG("contikimac: data (%u)\n", packetbuf_datalen()); NETSTACK_MAC.input(); return; } else { PRINTDEBUG("contikimac: data not for us\n"); } } else { PRINTF("contikimac: failed to parse (%u)\n", packetbuf_totlen()); } } /*---------------------------------------------------------------------------*/ #if CONTIKIMAC_CONF_ANNOUNCEMENTS static void send_announcement(void *ptr) { int announcement_len; int transmit_len; #if WITH_CONTIKIMAC_HEADER struct hdr *chdr; #endif /* WITH_CONTIKIMAC_HEADER */ /* Set up the probe header. */ packetbuf_clear(); announcement_len = format_announcement(packetbuf_dataptr()); if(announcement_len > 0) { packetbuf_set_datalen(announcement_len); 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 WITH_CONTIKIMAC_HEADER transmit_len = packetbuf_totlen(); if(packetbuf_hdralloc(sizeof(struct hdr)) == 0) { /* Failed to allocate space for contikimac header */ PRINTF("contikimac: send announcement failed, too large header\n"); return; } chdr = packetbuf_hdrptr(); chdr->id = CONTIKIMAC_ID; chdr->len = transmit_len; #endif /* WITH_CONTIKIMAC_HEADER */ if(NETSTACK_FRAMER.create()) { rtimer_clock_t t; int i, collisions; we_are_sending = 1; /* Make sure that the packet is longer or equal to the shorest packet length. */ transmit_len = packetbuf_totlen(); if(transmit_len < SHORTEST_PACKET_SIZE) { #if 0 /* Pad with zeroes */ uint8_t *ptr; ptr = packetbuf_dataptr(); memset(ptr + packetbuf_datalen(), 0, SHORTEST_PACKET_SIZE - transmit_len); #endif PRINTF("contikimac: shorter than shortest (%d)\n", packetbuf_totlen()); transmit_len = SHORTEST_PACKET_SIZE; } collisions = 0; /* Check for collisions */ for(i = 0; i < CCA_COUNT_MAX; ++i) { t = RTIMER_NOW(); on(); #if NURTIMER while(RTIMER_CLOCK_LT(t, RTIMER_NOW(), t + CCA_CHECK_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + CCA_CHECK_TIME)); #endif if(NETSTACK_RADIO.channel_clear() == 0) { collisions++; off(); break; } off(); #if NURTIMER while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t + CCA_SLEEP_TIME + CCA_CHECK_TIME)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + CCA_SLEEP_TIME + CCA_CHECK_TIME)) { } #endif } if(collisions == 0) { NETSTACK_RADIO.prepare(packetbuf_hdrptr(), transmit_len); NETSTACK_RADIO.transmit(transmit_len); t = RTIMER_NOW(); #if NURTIMER while(RTIMER_CLOCK_LT(t, RTIMER_NOW(), t + INTER_PACKET_INTERVAL)); #else while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + INTER_PACKET_INTERVAL)) { } #endif NETSTACK_RADIO.transmit(transmit_len); } we_are_sending = 0; } } } /*---------------------------------------------------------------------------*/ 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_snooping > 0) { is_snooping--; /* printf("is_snooping %d\n", is_snooping); */ } } /*---------------------------------------------------------------------------*/ static void listen_callback(int periods) { printf("Snoop\n"); is_snooping = periods + 1; } #endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ /*---------------------------------------------------------------------------*/ void contikimac_set_announcement_radio_txpower(int txpower) { #if CONTIKIMAC_CONF_ANNOUNCEMENTS announcement_radio_txpower = txpower; #endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ } /*---------------------------------------------------------------------------*/ static void init(void) { radio_is_on = 0; PT_INIT(&pt); #if NURTIMER rtimer_setup(&rt, RTIMER_HARD, (void (*)(struct rtimer *, void *, int status))powercycle, NULL); rtimer_schedule(&rt, CYCLE_TIME, 1); #else rtimer_set(&rt, RTIMER_NOW() + CYCLE_TIME, 1, (void (*)(struct rtimer *, void *))powercycle, NULL); #endif contikimac_is_on = 1; #if WITH_PHASE_OPTIMIZATION phase_init(&phase_list); #endif /* WITH_PHASE_OPTIMIZATION */ #if CONTIKIMAC_CONF_ANNOUNCEMENTS announcement_register_listen_callback(listen_callback); ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_TIME, cycle_announcement, NULL); #endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */ } /*---------------------------------------------------------------------------*/ static int turn_on(void) { if(contikimac_is_on == 0) { contikimac_is_on = 1; contikimac_keep_radio_on = 0; #if NURTIMER rtimer_schedule(&rt, CYCLE_TIME, 1); #else rtimer_set(&rt, RTIMER_NOW() + CYCLE_TIME, 1, (void (*)(struct rtimer *, void *))powercycle, NULL); #endif } return 1; } /*---------------------------------------------------------------------------*/ static int turn_off(int keep_radio_on) { contikimac_is_on = 0; contikimac_keep_radio_on = keep_radio_on; if(keep_radio_on) { radio_is_on = 1; return NETSTACK_RADIO.on(); } else { radio_is_on = 0; return NETSTACK_RADIO.off(); } } /*---------------------------------------------------------------------------*/ static unsigned short duty_cycle(void) { return (1ul * CLOCK_SECOND * CYCLE_TIME) / RTIMER_ARCH_SECOND; } /*---------------------------------------------------------------------------*/ const struct rdc_driver contikimac_driver = { "ContikiMAC", init, qsend_packet, input_packet, turn_on, turn_off, duty_cycle, }; /*---------------------------------------------------------------------------*/ uint16_t contikimac_debug_print(void) { static rtimer_clock_t one_cycle_start; printf("Drift %d\n", (one_cycle_start - cycle_start) % CYCLE_TIME); one_cycle_start = cycle_start; return 0; } /*---------------------------------------------------------------------------*/