How to determine from which Node a message is comming from

[TheoL]

First of all, not sure whether this is the right topic for my question, so if not I apologize.

I've been experimenting with node to node communication inspired by @GertSanders his presentation during the Dutch MySensors meetup. I haven't discovered this feature of MySensors before, but it's brilliant.

I can communicate from one sensor to another without the interference of any controller. Love it! It opens new possibilities, and probably keep me awake for a couple of nights ;-)

So I'd like to know, if there's a way to determine the sender of a message in the incomming message handler. I do see a setDestination() method but - at least in 1.5 - there's no getter and it seems like MySensors ignores that. For my use case it would be great if I can determine what the id is of the node of which the message is originating from.

I also tried to create a message with the default constructor like this:

  MyMessage myMsg(); 
  myMsg.setDestination( aNodeId );

but that results into the following compile error:

error: request for member 'setDestination' in 'myMsg', which is of non-class type 'MyMessage()'
   myMsg.setDestination( aNodeId );
         ^

I can get around that easily, so I think I misunderstood the API documentation for that.

void sendMessage( uint8_t aNodeId, char *aMsg ) {
  MyMessage myMsg( 255, V_VAR1 );
  myMsg.setDestination( aNodeId );
  myMsg.set( aMsg );
  gw.send( myMsg, true );
}

[mfalkvidd]

@TheoL this code:

void receive(const MyMessage &message) {
  
  LOG(F("Received %s from %s\n"), msgTypeAsCharRepresentation((mysensor_data)message.type), nodeTypeAsCharRepresentation(message.sender));

  delay(250);
  sendPingOrPongResponse( message );  
}

from the PingPong example suggests that the sender is available.

Is that a solution to your problem or did I not quite understand your question?

[TheoL]

@mfalkvidd Thanx for the quick reply and the example. It's exactly what I was I was looking for. I just overlooked the union definition in Message.h.

I'm currently sending the message to the Node itself as a test. But event that that works.