tx interrupt works, removed buffer delay related to discussion in #6

Author: paidforby

node.js

@@ -163,9 +163,12 @@ function Node(opts, radioOpts, routerOpts) {
       nodes[i]._rx(data);
     }
     this.transmitting = true;
+    var meta_flag = 1;
+    var metadata = "t1";
+    var a = Buffer.concat([new Buffer([meta_flag]), new Buffer([metadata.length]), new Buffer(metadata)]);
+    this.router.stdin.write(a);
     var time = this.radio.getPayloadTime(data);
     time = this.network.getSimulationTime(time);
-    this.transmitting = false;
 
     // Notify listeners that we're transmitting. The websocket server
     // listens for these events and forwards to connected viz clients.
@@ -181,6 +184,10 @@ function Node(opts, radioOpts, routerOpts) {
       if(this.opts.debug) {
         console.log('[node ' + this.id + '] transmission completed in ' + time + "ms");
       }
+      var meta_flag = 1;
+      var metadata = "t0";
+      var a = Buffer.concat([new Buffer([meta_flag]), new Buffer([metadata.length]), new Buffer(metadata)]);
+      this.router.stdin.write(a);
       cb();
       this.tx(); // send more packets if there are any queued
     }.bind(this), time);
@@ -228,7 +235,8 @@ function Node(opts, radioOpts, routerOpts) {
       return;
     }
 
-    var b = Buffer.concat([new Buffer([packet.length]), new Buffer(packet)]);
+    var meta_flag = 0;
+    var b = Buffer.concat([new Buffer([meta_flag]), new Buffer([packet.length]), new Buffer(packet)]);
     this.router.stdin.write(b);
   };
 

routers/base.c

@@ -72,6 +72,32 @@ int print_err(const char* format, ...) {
   return ret;
 }
 
+int begin_packet(){
+    if(transmitting == 1){
+        // transmission in progress, do not begin packet
+        return 0;
+    }else{
+        // transmission done, begin packet
+        return 1;
+    }
+}
+
+int parse_metadata(char* data, uint8_t len){
+    data[len] = '\0';
+    switch(data[0]){
+        case 't':
+            if(data[1] == '0'){
+                transmitting = 0;
+            }else{
+                transmitting = 1;
+            }
+            break;
+        default:
+            perror("invalid metadata");
+    }
+    return 0;
+}
+
 int send_packet(char* data, uint8_t len) {
 
   char packet[258];
@@ -111,6 +137,7 @@ int main(int argc, char **argv) {
   ssize_t ret;
   ssize_t len = 0;
   ssize_t got;
+  ssize_t meta = 0;
 
   nsleep(0, 0);
 
@@ -158,14 +185,20 @@ int main(int argc, char **argv) {
     }
 
     if(ret && FD_ISSET(STDIN, &fds)) {
+      if(!meta){
+        ret = read(STDIN, &meta, 1);
+        if(ret < 0) {
+          perror("failed to read metadata flag");
+          return 1;
+        }
+      }
       if(!len) {
         // receive the length of the incoming packet
         ret = read(STDIN, &len, 1);
         if(ret < 0) {
           perror("receiving length of incoming packet failed");
           return 1;
         }
-
         got = 0;
       }
 
@@ -185,9 +218,15 @@ int main(int argc, char **argv) {
         continue;
       }
 
-      if(ret = packet_received(buffer, len)) {
+      if(meta){
+        if(ret = parse_metadata(buffer, len)){
+          return ret;
+        }
+      }
+      else if(ret = packet_received(buffer, len)) {
         return ret;
       }
+      meta = 0;
       len = 0;
     }
 

routers/base.h

@@ -16,10 +16,14 @@ int print_err(const char* format, ...);
 
 int debug_printf(const char* format, ...);
 
+int begin_packet();
+
 int send_packet(char* data, uint8_t len);
 
 int nsleep(unsigned int secs, useconds_t usecs);
 
+int transmitting;
+
 // you must declare these in your router
 int setup(); // called once on startup
 int loop(); // called once per event loop iteration

routers/firmware.c

@@ -18,13 +18,9 @@ uint8_t messageCount = 0;
 
 // mode switches
 int retransmitEnabled = 0;
-int pollingEnabled = 0;
-int beaconModeEnabled = 1;
 int hashingEnabled = 1;
-int beaconModeReached = 0;
 
 // timeout intervals
-int bufferInterval = 3;
 int helloInterval = 10;
 int routeInterval = 10;
 int messageInterval = 5;
@@ -52,19 +48,13 @@ struct Packet {
     uint8_t data[240];
 };
 
+struct Packet buffer[8];
+int bufferEntry = 0;
+
 // table structures
 uint8_t hashTable[256][SHA1_LENGTH];
 uint8_t hashEntry = 0;
 
-/*
-struct BufferEntry {
-    uint8_t message[256]; 
-    uint8_t length;
-};
-*/
-struct Packet buffer[8];
-int bufferEntry = 0;
-
 struct NeighborTableEntry{
     uint8_t address[ADDR_LENGTH];
     uint8_t lastReceived;
@@ -154,21 +144,13 @@ struct Packet popFromBuffer(){
     return pop; 
 }
 
-long lastCheckTime = 0;
 void checkBuffer(){
 
-    if (time(NULL) - lastCheckTime > bufferInterval) {
-        if (bufferEntry > 0){
-            // Uncomment if you want race condition to determine a single beacon node
-            if(!beaconModeReached){
-                beaconModeEnabled = 0;
-            }
-            struct Packet packet = popFromBuffer();
-            sendPacket(packet);
-        }else{
-            debug_printf("Buffer is empty\n");
-        }
-        lastCheckTime = time(NULL);
+    if (bufferEntry > 0){
+        struct Packet packet = popFromBuffer();
+        sendPacket(packet);
+    }else{
+        debug_printf("Buffer is empty\n");
     }
 }
 
@@ -267,12 +249,10 @@ uint8_t calculateMetric(int entry, uint8_t sequence, struct Metadata metadata){
     float weightedRSSI =  ((float) metadata.rssi)*RSSIWeight;
     float weightedSNR =  ((float) metadata.snr)*SNRWeight;
     uint8_t metric = weightedPacketSuccess+weightedRSSI+weightedSNR;
-    /*
-    Serial.printf("weighted packet success: %3f\n", weightedPacketSuccess);
-    Serial.printf("weighted RSSI: %3f\n", weightedRSSI);
-    Serial.printf("weighted SNR: %3f\n", weightedSNR);
-    Serial.printf("metric calculated: %3d\n", metric);
-    */
+    debug_printf("weighted packet success: %3f\n", weightedPacketSuccess);
+    debug_printf("weighted RSSI: %3f\n", weightedRSSI);
+    debug_printf("weighted SNR: %3f\n", weightedSNR);
+    debug_printf("metric calculated: %3d\n", metric);
     return metric;
 }
 
@@ -519,7 +499,6 @@ long lastHelloTime = 0;
 void transmitHello(){
 
     if (time(NULL) - lastHelloTime > helloInterval) {
-        beaconModeReached = 1; 
         char data[240];
         char message[10] = "Hola from\0";
         sprintf(data, "%s %s", message, macaddr);
@@ -686,29 +665,31 @@ int setup() {
 int state = 0;
 int loop() {
 
-    // State machine for testing purposes
-    if(state == 0){
-        Serial.printf("learning... %d", time(NULL) - startTime);
-        printNeighborTable();
-        printRoutingTable();
-        transmitHello();
-        if (time(NULL) - startTime > discoveryTimeout) {
-            state++;
-        }
-    }else if(state == 1){
-        Serial.printf("learning... %d", time(NULL) - startTime);
-        printNeighborTable();
-        printRoutingTable();
-        transmitRoutes();
-        if (time(NULL) - startTime > learningTimeout) {
-            state++;
-        }
-    }else if(state == 2){
-        checkBuffer(); 
-        if(chance == 3){
-            transmitToRandomRoute();        
+    if(!begin_packet()){
+        Serial.printf("transmit in progress please wait");
+    }else{
+        if(state == 0){
+            Serial.printf("learning... %d", time(NULL) - startTime);
+            printNeighborTable();
+            printRoutingTable();
+            transmitHello();
+            if (time(NULL) - startTime > discoveryTimeout) {
+                state++;
+            }
+        }else if(state == 1){
+            Serial.printf("learning... %d", time(NULL) - startTime);
+            printNeighborTable();
+            printRoutingTable();
+            transmitRoutes();
+            if (time(NULL) - startTime > learningTimeout) {
+                state++;
+            }
+        }else if(state == 2){
+            checkBuffer(); 
+            if(chance == 3){
+                transmitToRandomRoute();        
+            }
         }
     }
-
     nsleep(1, 0);
 }