On Mar 15, 2011, at 12:00 PM, Breno Guimarães wrote: > Hi, > > I'm working with MicaZ motes on TinyOS 2.0.1. > > My application is simple. I have one mote sending a broadcast message and > other two responding to the first whenever they receive any message. > Therefore, the first mote receive two messages almost at the same time. > > When running on TOSSIM, I noticed that they respond exactly at the same time. > As the first mote can't receive two messages at the same time, it drops one > of the messages. > > I solved this problem by using a timer on each mote that acts as a "clock". > The clock frequency is calculated using the node ID number, so every mote > respond with different times. > > That works very well on the simulation and there was no problem when I tried > on real motes. > But that seems a poor solution as it is made on software. > > My question is: Is there any hardware that avoid that kind of problem on > micaz? If there isn't, is there any other better software solution?
You're basically introducing time slots at a higher layer. That's a reasonable approach although it has limitations with respect to how many nodes it can support. Another approach is to just try retransmitting failed packets. The TinyOS MAC is such that if there are only 2 nodes it should not take more than a handful of retransmissions in the absolute worst case (unless you are sending very long packets). Phil _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
