X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=tos%2Flib%2Fftsp%2FTimeSyncP.nc;h=6a17381db172e17fc18e04081fc29f3bca3ad3e8;hb=e9bfab607e051bae6afb47b44892ce37541d1b44;hp=fc2ef9944e57cc1a05c1a7c9782cd2dc318f96ce;hpb=1b3430016a83abd7c0deaaa08b86e93ad049fb2d;p=tinyos-2.x.git diff --git a/tos/lib/ftsp/TimeSyncP.nc b/tos/lib/ftsp/TimeSyncP.nc index fc2ef994..6a17381d 100644 --- a/tos/lib/ftsp/TimeSyncP.nc +++ b/tos/lib/ftsp/TimeSyncP.nc @@ -43,9 +43,16 @@ generic module TimeSyncP(typedef precision_tag) interface TimeSyncAMSend as Send; interface Receive; interface Timer; + interface Random; interface Leds; interface TimeSyncPacket; interface LocalTime as LocalTime; + + +#ifdef LOW_POWER_LISTENING + interface LowPowerListening; +#endif + } } implementation @@ -61,7 +68,7 @@ implementation IGNORE_ROOT_MSG = 4, // after becoming the root ignore other roots messages (in send period) ENTRY_VALID_LIMIT = 4, // number of entries to become synchronized ENTRY_SEND_LIMIT = 3, // number of entries to send sync messages - ENTRY_THROWOUT_LIMIT = 100, // if time sync error is bigger than this clear the table + ENTRY_THROWOUT_LIMIT = 500, // if time sync error is bigger than this clear the table }; typedef struct TableItem @@ -150,6 +157,8 @@ implementation float newSkew = skew; uint32_t newLocalAverage; int32_t newOffsetAverage; + int32_t localAverageRest; + int32_t offsetAverageRest; int64_t localSum; int64_t offsetSum; @@ -169,16 +178,23 @@ implementation newOffsetAverage = table[i].timeOffset; localSum = 0; + localAverageRest = 0; offsetSum = 0; + offsetAverageRest = 0; while( ++i < MAX_ENTRIES ) if( table[i].state == ENTRY_FULL ) { + /* + This only works because C ISO 1999 defines the signe for modulo the same as for the Dividend! + */ localSum += (int32_t)(table[i].localTime - newLocalAverage) / tableEntries; + localAverageRest += (table[i].localTime - newLocalAverage) % tableEntries; offsetSum += (int32_t)(table[i].timeOffset - newOffsetAverage) / tableEntries; + offsetAverageRest += (table[i].timeOffset - newOffsetAverage) % tableEntries; } - newLocalAverage += localSum; - newOffsetAverage += offsetSum; + newLocalAverage += localSum + localAverageRest / tableEntries; + newOffsetAverage += offsetSum + offsetAverageRest / tableEntries; localSum = offsetSum = 0; for(i = 0; i < MAX_ENTRIES; ++i) @@ -218,8 +234,6 @@ implementation uint32_t age, oldestTime = 0; int32_t timeError; - tableEntries = 0; - // clear table if the received entry's been inconsistent for some time timeError = msg->localTime; call GlobalTime.local2Global((uint32_t*)(&timeError)); @@ -229,10 +243,11 @@ implementation { if (++numErrors>3) clearTable(); + return; // don't incorporate a bad reading } - else - numErrors = 0; + tableEntries = 0; // don't reset table size unless you're recounting + numErrors = 0; for(i = 0; i < MAX_ENTRIES; ++i) { age = msg->localTime - table[i].localTime; @@ -269,7 +284,7 @@ implementation if( msg->rootID < outgoingMsg->rootID && // jw: after becoming the root ignore other roots messages (in send period) - ~(heartBeats < IGNORE_ROOT_MSG && outgoingMsg->rootID == TOS_NODE_ID) ){ + !(heartBeats < IGNORE_ROOT_MSG && outgoingMsg->rootID == TOS_NODE_ID) ){ outgoingMsg->rootID = msg->rootID; outgoingMsg->seqNum = msg->seqNum; } @@ -302,7 +317,9 @@ implementation if( diff < -16 || diff > 16 ) return msg; #endif - if( (state & STATE_PROCESSING) == 0 ) { + + if( (state & STATE_PROCESSING) == 0 + && call TimeSyncPacket.isValid(msg)) { message_t* old = processedMsg; processedMsg = msg; @@ -343,7 +360,9 @@ implementation } outgoingMsg->globalTime = globalTime; - +#ifdef LOW_POWER_LISTENING + call LowPowerListening.setRemoteWakeupInterval(&outgoingMsgBuffer, LPL_INTERVAL); +#endif // we don't send time sync msg, if we don't have enough data if( numEntries < ENTRY_SEND_LIMIT && outgoingMsg->rootID != TOS_NODE_ID ){ ++heartBeats; @@ -396,11 +415,8 @@ implementation } command error_t TimeSyncMode.setMode(uint8_t mode_){ - if (mode == mode_) - return SUCCESS; - - if (mode_ == TS_USER_MODE){ - call Timer.startPeriodic((uint32_t)1000 * BEACON_RATE); + if (mode_ == TS_TIMER_MODE){ + call Timer.startPeriodic((uint32_t)(896U+(call Random.rand16()&0xFF)) * BEACON_RATE); } else call Timer.stop(); @@ -448,10 +464,9 @@ implementation command error_t StdControl.start() { - mode = TS_TIMER_MODE; heartBeats = 0; outgoingMsg->nodeID = TOS_NODE_ID; - call Timer.startPeriodic((uint32_t)1000 * BEACON_RATE); + call TimeSyncMode.setMode(TS_TIMER_MODE); return SUCCESS; }