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 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