DCC:setThrottle can return bool for success (loco found or created) or not

Author: habazut

DCC.cpp

@@ -97,18 +97,18 @@ byte DCC::getMomentum(LocoSlot * slot) {
    return (slot->getMomentumD() == MOMENTUM_USE_DEFAULT) ? defaultMomentumD : slot->getMomentumD();
 }
 
-void DCC::setThrottle( uint16_t cab, uint8_t tSpeed, bool tDirection)  {
+bool DCC::setThrottle( uint16_t cab, uint8_t tSpeed, bool tDirection)  {
   if (tSpeed==1) {
     if (cab==0) {
       estopAll(); // ESTOP broadcast fix 
-      return;
+      return true;
     }
   } 
   byte speedCode = (tSpeed & 0x7F)  + tDirection * 128;
   auto slot=LocoSlot::getSlot(cab, true);
-  if (!slot) return; // speed table full, can not do anything
+  if (!slot) return false; // speed table full, can not do anything
   if (slot->getTargetSpeed()==speedCode) // speed has been reached
-    return;
+    return true;
   slot->setTargetSpeed(speedCode);
   byte momentum=getMomentum(slot);
   if (momentum && tSpeed!=1) { // not ESTOP
@@ -121,6 +121,7 @@ void DCC::setThrottle( uint16_t cab, uint8_t tSpeed, bool tDirection)  {
     TrackManager::setDCSignal(cab,speedCode); // in case this is a dcc track on this addr
   }
   CommandDistributor::broadcastLoco(slot);
+  return true;
 }
 
 void DCC::setThrottle2( uint16_t cab, byte speedCode)  {
@@ -1208,4 +1209,4 @@ void DCC::clearBlock(uint16_t blockid) {
         }
       }
   #endif
-}
+}

DCC.h

@@ -50,7 +50,7 @@ class DCC
   static void loop();
 
   // Public DCC API functions
-  static void setThrottle(uint16_t cab, uint8_t tSpeed, bool tDirection);
+  static bool setThrottle(uint16_t cab, uint8_t tSpeed, bool tDirection);
   static void estopAll();
   static int8_t getThrottleSpeed(int cab);
   static uint8_t getThrottleSpeedByte(int cab);

DCCEXParser.cpp

@@ -376,11 +376,14 @@ void DCCEXParser::parseOne(Print *stream, byte *com, RingStream * ringStream)
 	if (cab > 10239 || cab < 0)
 	    break; // beyond DCC range
 
-        DCC::setThrottle(cab, tspeed, direction);
-        if (params == 4) // send obsolete format T response
+        if (DCC::setThrottle(cab, tspeed, direction)) {
+	  if (params == 4) // send obsolete format T response
             StringFormatter::send(stream, F("<T %d %d %d>\n"), p[0], p[2], p[3]);
-        // speed change will be broadcast anyway in new <l > format
-        return;
+	  // speed change will be broadcast anyway in new <l > format
+	  return;
+	} else {
+	  break; // setThrottle() failed means slot table was full.
+	}
     }
     case 'f': // FUNCTION <f CAB BYTE1 [BYTE2]>
         if (parsef(stream, params, p))