hello,

I have noticed that in TOSSIM, if a mote is busy receiving a packet, then a 
newly received packet will be discarded, however, the fisrt packet will be 
received successfuly.  Does this means that collissions are not possible in 
TOSSIM? attached is the code from the CpmModelC.nc file which is responsible 
for the receiving of a packet:

   // If I'm off, I never receive the packet, but I need to keep track of
    // it in case I turn on and someone else starts sending me a weaker
    // packet. So I don't set receiving to 1, but I keep track of
    // the signal strength.
    if (!sim_mote_is_on(sim_node())) { 
      dbg("CpmModelC", "Lost packet from %i due to %i being off\n", source, 
sim_node());
      rcv->lost = 1;
    }
    else if (!shouldReceive(power - noiseStr)) {
      rcv->lost = 1;
    }
    else if (receiving) {
      rcv->lost = 1;
    }
    else {
      receiving = 1;
      rcv->next = outstandingReceptionHead;
      outstandingReceptionHead = rcv;
      evt = allocate_receive_event(endTime, rcv);
      sim_queue_insert(evt);
    }


      
____________________________________________________________________________________
Never miss a thing.  Make Yahoo your home page. 
http://www.yahoo.com/r/hs
_______________________________________________
Tinyos-help mailing list
Tinyos-help@Millennium.Berkeley.EDU
https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help

Reply via email to