Thanks for sending those measurements. It looks like the radio is doing its job duty cycling. I'm not sure about what would cause the packet losses, but one possibility for the discrepancies in the length of T1/T2 is the receiver's receive check. If the receiver detects the transmission and ack's back, the transmission will be cut short. Therefore, the length of transmission could vary from send to send.
The 4.4 mA is definitely high, but shows the radio is not on. I would suspect the microcontroller is not entering a deep sleep like it should. I'll start working with this soon (soon being late this week or next) to see what results I come up with. -David -----Original Message----- From: Ravi Prasad [mailto:[EMAIL PROTECTED] Sent: Sunday, August 05, 2007 6:49 PM To: David Moss Cc: [email protected] Subject: RE: [Tinyos-help] Again!!!! Low-power CC2420 multihop in TinyOS2.xquestion???? Hi David, I used oscilloscope to check the power consumtion. I am measuring voltage drop across a small resistor connected in series to the Vcc input from battery. Following are the results I get with CTP-LPL in micaz: Current ^ | <-T1 -> | |-----| |-------|C1 | | |<-T2-> | | | ----| |-------| |-----C2 --------------------------------------------> time T1 = time period when current consumption is high T2 = time period when current consumption is low C1 = Current when mote is in wake up mode C2 = Current when mote is sleeping Case 1. RxSleep = Localsleep = 1 sec Periodic packet sending period = 1 sec Power consumption: T1 ~= 132ms, T2 ~= 820ms, C1 ~=28.4mA, C2 ~= 4.4 mA Case 2. RxSleep = Localsleep = 1 sec Periodic packet sending period = 10 sec Power consumption: T1 ~= 1s, T2 ~= 20s, C1 ~=28.4mA, C2 ~= 4.4 mA In case 2, the graph in oscilloscope was not very consistent. The values of T1 and T2 were changing a lot. Also there were approx 10 spikes in the region where mote was sleeping. I guess it was due to the periodic beaconing in CTP routing protocol. Also there were few packet losses. The above stated values are average values. Case 3. RxSleep = Localsleep = 10 sec Periodic packet sending period = 10 sec Power consumption: T1 = 3 to 10s, T2 = 50 to 80s, C1 ~=30mA, C2 ~= 6.8 mA In case 3 also, the graph in oscilloscope was not very consistent. The values of T1 and T2 were changing a lot. Also there were approx 20 to 40 spikes in the region where mote was sleeping. Also there were many packet losses. I tried with LplUnicast and LplBroadcast also. In that case the sleep current was ~=400uA. This is also not very low but is fairly good. I am not able to find why there is so huge diffenrence in power consumption between CTP and LPLUnicast. Regards Ravi --- David Moss <[EMAIL PROTECTED]> wrote: > Hi Ravi, > > What is the rxInterval you're setting? And what are > you using the measure > the current consumption? > > -David > > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > On Behalf Of Ravi > Prasad > Sent: Friday, August 03, 2007 2:30 AM > To: [EMAIL PROTECTED] > Cc: Philip Levis; > [email protected] > Subject: Re: [Tinyos-help] Again!!!! Low-power > CC2420 multihop in > TinyOS2.xquestion???? > > > > Hi Roman, > > Thank you. > > Have you tested your modified CTP using CC2420LPL?? > What was the power consumption?? > > I also used another approach ( a dirty quick fix, > but > it was fastest approach) for using LPL in CTP. I > modified the DefaultLpl.nc file to use a specified > sleep period for all packets it transmitts. As every > packet passes through this layer, this sleep period > is > applied to all Tx packets. > > This approach is performimg duty cycle but the power > consumption is again very huge. The lowest > consumption > is 4mA. > > The power consumption is same as was in case when I > set the Rx sleep perion in top level application > only > for the application level packet. This I stated in > my > previous email. > > So untill now I am not able to get the 200-400uA > sleep > current in CTA. > > What do you suggest to get lower power consumtion? > > Or again same question--Do you think I should try > another multihop routing protocol over CC2420 LPL?? > > > Regards > Ravi > > > --- Roman Lim <[EMAIL PROTECTED]> wrote: > > > Hi > > > > In order to use lpl with ctp you could modify the > > ctpforwarding engine > > and add the lpl information for transmission. > > I added an interface where you can tell the ctp > > layer to use a default > > rx sleep interval for forwarded packets. > > > > roman > > > > Ravi Prasad wrote: > > > Dear Philip, > > > > > > Thank you for your reply. > > > > > > As you said that CC2420 LPL in Tinyos2.x works > > with > > > arbitrary topologies, I tried to use LPL with > > > collection protocol provided in tinyos2.0.2. I > > used > > > the LowPowerListening interface in my top level > > > application to set the sleep interval of TX and > > Rx > > > sides. The application somehow worked with one > > > transmitter & one receiver. But the lowest > current > > > consumption was 4mA which is very huge. Also the > > > initial tree formation time is very big. If I > use > > a > > > sleep interval of more than 3seconds the tree > > dosent > > > even forms and nothing works. > > > > > > I think as the CollectionTree also uses > > ActiveMessage > > > to send/receive data/routing packets, the > > > sleepinterval setting should be controlled at a > > single > > > point from where all packets (i.e routing and > > data) > > > flow, that is the ActiveMessage component. > > > > > > Can you please comment on the above? > > > > > > Also it would be great if you have some > suggestion > > to > > > use another multihop routing on top of > CC2420LPL. > > > > > > > > > Regards > > > Ravi > > > --- Philip Levis <[EMAIL PROTECTED]> wrote: > > > > > >> Ravi Prasad wrote: > > >>> Hi all, > > >>> > > >>> My need - Low power multihop for CC2420 (with > > >>> Atmega128 mcu i.e micaz).. > > >>> > > >>> > > >>> Low power CC2420 is being asked so many times > in > > >> this > > >>> list. I have been working on TinyOS1.x and in > > that > > >> low > > >>> power CC2420 was not really available. > > >>> > > >>> Now I have switched to TinyOS2.x and I know > that > > >> there > > >>> is a LPL implementation of CC2420. But it > seems > > >> that > > >>> is for a Star network topology & not used in > any > > >>> multihop routing protocol. Am I right?? > > >>> > > >> The CC2420 LPL in 2.x works for arbitrary > > >> topologies. > > >> > > >> Phil > > >> > > > > > > > > > > > > > > > > > > ____________________________________________________________________________ > ________ > > > Choose the right car based on your needs. Check > > out Yahoo! Autos new Car Finder tool. > > > http://autos.yahoo.com/carfinder/ > > > _______________________________________________ > > > Tinyos-help mailing list > > > [email protected] > > > > > > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > > > > > > > > > ____________________________________________________________________________ > ________ > Park yourself in front of a world of choices in > alternative vehicles. Visit > the Yahoo! Auto Green Center. > http://autos.yahoo.com/green_center/ > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > > > ____________________________________________________________________________ ________ Moody friends. Drama queens. Your life? Nope! - their life, your story. Play Sims Stories at Yahoo! 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