It is ultimately sent using the CSMA MAC protocol but not CSMA/CA. So clear channel assessment is done, initial, congestion, random backoffs are used but RTS/CTS are not used Acks can be requested however To learn nore, see the CC2420CsmaP.nc in tos/chips/CC2420/cmsa and CC2420TransmitP.nc in tos/chips/CC2420/transmit and CC2420 datasheet page 51 (right column mid) http://enaweb.eng.yale.edu/drupal/system/files/CC2420_Data_Sheet_1_4.pdf
CC2420 has a hardware level facility to automatically check for CCA(clear channel assessment) and transmit in STXONCCA mode. This facility is used in attemptSend() method of CC2420TransmitP.nc Regards Abhishek Anand alt email: [EMAIL PROTECTED] http://abhishek.anand.iitg.googlepages.com/home On Mon, Jun 9, 2008 at 6:41 AM, Shikhar Sachan <[EMAIL PROTECTED]> wrote: > Hello All, > > I had a small question. Hope to receive an answer soon. What happens > when I issue a send command to transmit a packet. > Does it hand over the packet to the MAC layer which in turn uses the > CSMA/CA scheme with random backoff or does it just transmit the packet > on the media. > > Shikhar > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >
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