The RadioBackoff interface is designed to allow (possible several) modules in your application layer to listen in on what the radio stack is doing, and decide whether or not to affect the operation of CSMA. Unlike the former CsmaBackoff interface, a module is not required to affect the operation of CSMA if it is simply listening for a specific case to arise.
The RadioBackoff.requestInitialBackoff() event is signaled right before the message is attempting to send the first time. If the channel is found to be busy, CSMA will hold off on transmitting in a "congestion backoff". Each subsequent congestion backoff that occurs while the channel is busy will result in the RadioBackoff.requestCongestionBackoff() event signaling. If you are interested in affecting the backoff times of CSMA, you MUST call back to the RadioBackoff interface INSIDE the event that fired. In other words, if you get a requestInitialBackoff() event and you're interested in changing the initial backoff delay, you call back only inside that event RadioBackoff.setInitialBackoff(...). Same thing with the requestCongestionBackoff() event - you must call back to RadioBackoff.setCongestionBackoff() inside the event if you want to affect operation. If you call the commands outside of an event, they will be ignored. Similarly, if you call back with the wrong command inside an event (like calling setCongestionBackoff() inside the requestInitialBackoff() event) it will be ignored. -David -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of sergio mena doce Sent: Monday, March 10, 2008 7:16 AM To: tinyos-help@millennium.berkeley.edu Subject: [Tinyos-help] How to use interface RadioBackoff Hello, I'm working in tinyos application and I'd like to modify the backoff interval to do several communication test between motes. I don't understand fine how to use the interface RadioBackoff provided by the component CC2420CsmaC. When do requestInitialBackoff and requestCongestionBackoff events fires? When can I implement the setInitialBackoff and setCongestionBackoff? Can these commands go inside or outisde of the events? I hope your reply. Thanks. _________________________________________________________________ MSN Video. http://video.msn.com/?mkt=es-es _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
