Patch incorporate changes on CVS head through 8/23/09 for tos/lib/ftsp only.

[tinyos-2.x.git] / tos / lib / ftsp / TimeSyncP.nc

diff --git a/tos/lib/ftsp/TimeSyncP.nc b/tos/lib/ftsp/TimeSyncP.nc
index fc2ef9944e57cc1a05c1a7c9782cd2dc318f96ce..3c3affe83d12528d0d7ef1ece43dfbe316742875 100644 (file)
--- a/tos/lib/ftsp/TimeSyncP.nc
+++ b/tos/lib/ftsp/TimeSyncP.nc
@@ -46,6 +46,12 @@ generic module TimeSyncP(typedef precision_tag)
         interface Leds;
         interface TimeSyncPacket<precision_tag,uint32_t>;
         interface LocalTime<precision_tag> as LocalTime;
+
+
+#ifdef LOW_POWER_LISTENING
+        interface LowPowerListening;
+#endif
+
     }
 }
 implementation
@@ -61,7 +67,7 @@ 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 +156,8 @@ implementation
         float newSkew = skew;
         uint32_t newLocalAverage;
         int32_t newOffsetAverage;
+        int32_t localAverageRest;
+        int32_t offsetAverageRest;
 
         int64_t localSum;
         int64_t offsetSum;
@@ -169,16 +177,23 @@ 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 +233,6 @@ 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 +242,11 @@ 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;
@@ -302,7 +316,8 @@ 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;
@@ -344,6 +359,9 @@ implementation
 
         outgoingMsg->globalTime = globalTime;
 
+#ifdef LOW_POWER_LISTENING
+        call LowPowerListening.setRxSleepInterval(&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;
@@ -399,7 +417,7 @@ implementation
         if (mode == mode_)
             return SUCCESS;
 
-        if (mode_ == TS_USER_MODE){
+        if (mode_ == TS_TIMER_MODE){
             call Timer.startPeriodic((uint32_t)1000 * BEACON_RATE);
         }
         else