thanks for your answer. When i say RxTxDelay I mean the amount of time the radio takes to change from RX to TX mode (or vice versa). Theorically ,after sending a message, the radio should turn from Ttransfer mode to Receive mode, and then (when it must transmit a message) turn from Receive mode to Transmit mode. I'm wondering to know how much time radio needs to switch from RX to TX mode (or vice versa), cause the default value founded in tossim ( "opt\tinyos-2.x\tos\lib\tossim\sim_csma.h" ) is about 170 us ( 0,167 ms ).
What is this RxTxDelay? and the value in opt\tinyos-2.x\tos\lib\tossim\sim_csma.h is correct for TmoteSky motes or it's too low? thanks for your answer. best regards Bye 2008/6/12 Abhishek Anand <[EMAIL PROTECTED]>: > No the radio is not turned off by default after sending every message. > Even if you have defined LOW_POWER_LISTENING, the radio is turned on and > off regularly maintaining a duty cycle. I dont know what RxTxDelay is. It > had no mention in the CC2420 datasheet. > And I tested experimentally the radio starting time on my micaz motes.... > the reults are appended > > (you can see that the diff b/w startCommandIssueTime and startDoneTime is > always 2ms) > (note that the value 2ms is accurate only to the order of milliseconds) > > Messsage <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 252] > [startDoneTime= 254] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 502] > [startDoneTime= 504] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 752] > [startDoneTime= 754] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 1002] > [startDoneTime= 1004] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 1252] > -- INSERT -- > Messsage <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 252] > [startDoneTime= 254] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 502] > [startDoneTime= 504] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 752] > [startDoneTime= 754] > --------------------------------------- > Message <BlinkToRadioMsg> > [nodeid=0x1] > [startCommandIssueTime= 1002] > [startDoneTime= 1004] > > > > On Thu, Jun 12, 2008 at 6:23 PM, salvatore galati <[EMAIL PROTECTED]> > wrote: > >> Hi all. >> Sorry for my frequent questions. >> I'm a student of Informatic Engeenering of University of Pisa. >> I'm working with TmoteSky motes and TinyOs 2.x on cygwin. >> >> I founded a difference between my tossim simulation and realt tests with >> motes. >> In Tossim simulation the average message transmission time is about 6,8 ms >> In TmoteSky the average transmission time is about 10 ms. >> >> I found in >> http://csl.stanford.edu/~pal/pubs/tinyos-programming.pdf<http://csl.stanford.edu/%7Epal/pubs/tinyos-programming.pdf> >> that >> time to turn on/off the CC2420 radio is about: >> >> 1.) 0.6ms ------> Turn on the voltage regulator >> 2.) X ms (depends on contention) ------> Acquire the SPI bus to the >> radio >> 3.) 0.86ms ------> Start the radio's oscillator by sending a command >> over the bus (0.86ms) >> 4.) 0.2ms ------> Put the radio in RX mode (0.2ms) >> >> so total time to turn on/off radio is about ( minimum value ) 1,66 ms >> >> My question are : >> -- This time is the RxTxDelay ? so after sending a message the radio >> turns alway off and then turns on? >> -- This time to turn on/off radio is the same for micaz and >> telosb/TmoteSky motes? >> >> If this time is the RxTxDelay--->so dafault value in Tossim "mac" object >> ( = 0,18 ms from "opt\tinyos-2.x\tos\lib\tossim\sim_csma.h" ) >> is too low respect to this value of 1,66ms , it can be possible that >> difference, between average transmission >> time in tossim and in motes, is caused by this too low RxTxDelay default >> value in tossim configuration parameters for a CSMA link.? >> >> thanks very much for your answers >> >> Best Regards >> >> Bye Salvatore. >> >> _______________________________________________ >> Tinyos-help mailing list >> Tinyos-help@millennium.berkeley.edu >> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >> > >
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