(TinyOS 2.0.2; Micaz; mib510; Cygwin) I have left a number of motes running in low power listening mode and have observed that occasionally one or more of the motes' LPL-receive-check experiences a sudden delay/shift of approximately 100 ms and shortly thereafter a second sudden delay/shift of approximately 100-120 ms. I am not running any transmitters although 2.4 GHz is quite a popular frequency... the first time I observed it two motes experienced the delay at the same time after three minutes of running, the second time I observed it a single Mote experienced the delay after approximately half an hour, and this morning one of the three motes I had left running had experienced this delay at some point overnight. One of the three motes experienced this delay in all three tests, one of the motes did not experience the delay at all, and the third Mote experienced the delay once in the first test but not again. When two motes experienced the delay, they experienced it at what appeared to be the same time and the delay was consistent between them.
Is there a built-in function within low power listening that initiates a timeout/delay-of-start with regards to the sleep interval timer that lasts approximately 100 ms, perhaps to cope with noisy channels or received packets/suspected received packets? Signal detection as opposed to a random software/hardware error is because I have observed (using an oscilloscope) two motes undergoing the exact same delay at the exact same time. The receive event is not triggered and therefore I assume that this is some function to deal with a suspected packet when energy is detected. Would it be a trivial matter for me to find this function such that I could add an event trigger so that I know every time that LPL detects Channel energy but subsequently does not receive a packet (assuming this is what is causing the delay). Perhaps something like "FalseReceive" - this might allow me to correct the timing within my programme whenever this delay occurs. Also, if I could be directed to the exact function that would be very useful would as it might save me a lot of time trawling through code/editing something incorrectly ;-) Many thanks Ben ******************************************************************************* Please consider the environment before printing this email. ******************************************************************************* This email and any files transmitted with it are intended solely for the use of the individual or entity to whom they are addressed and may not be divulged to any third party without the express permission of the originator. Any views expressed in this message are those of the individual sender, except where the sender specifically states them to be the views of Thales Research & Technology (UK) Limited. ******************************************************************************* _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
