Hi!

On Mon, 9 Nov 2009, Giorgio Galassi (giorgio.galassi) wrote:

> I send 3 packet (length 28 byte) of 1 that is 84  ones then I send  3 
> packets of 2s and go on untill 100 .So I think of receive at the 
> basestation 84 ones then 84 twos  then 84 threes untill 100 but 
> sometimes I received 84 ones and then 92 twos for example and then 84 
> trees. I don't understand why I obtain 92 twos when I have to receive 
> 84.

This is indeed strange. How do you determine the length of the packet when 
you send it on the serial? A bug in that part might explain the strange 
value. :P

--
Razvan ME

> This happen when I use batteries because when I use usb cable to 
> power tmote this problem don't happen. I use packetacknoledge of 
> CC2420ActivemessageC to know if a packet is received corretcly and if I 
> don't receive  ack of  the packet send in th sendDone event I retransmit 
> it .Tomorrow I try to use packetlink as You suggeste.
> Thank you very much Razvan ME :I think that you have already help me in the 
> past.
>
> Bye
>
> Giorgio
>
>
> ----- Messaggio Originale -----
> Da: "Razvan Musaloiu-E." <[email protected]>
> Data: Lunedi', Novembre 9, 2009 9:15 pm
> Oggetto: Re: [Tinyos-help] packet ack
> A: giorgio <[email protected]>
> Cc: [email protected]
>
>> Hi!
>>
>> On Mon, 9 Nov 2009, giorgio wrote:
>>
>>> I have a node that send packet to a base station and use packet acknoledge 
>>> to
>>> know if a packet it is send or not .So I use CC2420ActivemessageC as 
>>> component
>>> and use his interface PacketAcknowledgements :
>>> what I don't understand is why sometimes not always when the node sender not
>>> receive the ack and resend the same packet the node basestation receive a
>>> piece of the same packet plus the same packet full.
>>
>> Can you be more specific about what "a piece of the the same packet"
>> means?
>>
>>> It seems that also it has not received the packet according the
>>> packetacknoledgement it has receive a piece of it .This behaviour is
>>> very rare if I use usb cable to power the tmote but more usual when I
>>> use rechargeble batteries ?It appear as false ack. Someone know to solve
>>> this problem or know what is the right strategy to use with
>>> packetacknolegments ?
>>>
>>
>> Have you tried to use the PacketLink interface? The PacketLink takes care
>> of retransmitting the packet and filtering the duplicates.
>>
>> --
>> Razvan ME
>>
>
_______________________________________________
Tinyos-help mailing list
[email protected]
https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help

Reply via email to