[Tinyos-help] [TinyOS-Help]:What is the usage of "DCC2420_NO_ACKNOWLEDGEMENTS"??

[Razvan Musaloiu-E.]

Hi!

On Wed, 24 Sep 2008, Renee Azhen wrote:

> Does this flag(CC2420_NO_ACKNOWLEDGEMENTS) is used by mac/link layer?
> if the CC2420_NO_ACKNOWLEDGEMENTS was set, then no ack will be sent by 
> receiver, so the receive.Done event will always return true?

You are talking about AMSend.sendDone? AMSend.sendDone will not return a 
fail even if the packet is not acked. To check for that you have to use 
the wasAcked from the PacketAcknowledgements interface 
(PacketAcknowledgements.nc from tos/interfaces). You also need to use the 
requestAck from it before doing a AMSend.send of the packet.

--
Razvan ME

> Tony O'Donovan <tonyodon at yahoo.com>
> When a sender tranmits a message to a receiver the receiver can send an 
> acknowledgment (ACK) message. The purpose of the ACK is to let the 
> sender know the message was successfully received. If the 
> CC2420_NO_ACKNOWLEDGEMENTS option is set the receiver does not send an 
> ACK when it receives a message.
>
>
> --- Renee Azhen  wrote:
>
>> hi, all,
>> I am using the collection protocol, and found that
>> if I use:
>> CFLAGS += -DCC2420_NO_ACKNOWLEDGEMENTS
>> CFLAGS += -DCC2420_NO_ADDRESS_RECOGNITION
>> in the app makfile, network almost failed, it can't
>> deliver any packet.
>>
>> So is there anyone know what is the usage of that
>> line in Makefile??
>>
>> thanks
>> Sam
>>
>>