Is there any way to shorten the Network Watchdog Timer for under 3 minutes?

Is it possible to shorten the Network Watchdog Timer so a roouter can leave a coordinator-less network under 3 minutes (3NW1 minute)?

Not on its own. But you can issue a local or Global network reset when ever you want. Just understand that this does affect the memory of the module and doing so can and will reduce the life expediency by wearing down the non flash memory.

So is it also reset all the parameter of the XBee? Where can i find the reference about this network reset? Thank you very much.

what about ‘FR’ command (software reset)? Does it have the same effect with network reset? Thank you.

No the NR only does a Network reset. It does not affect any other commands beyond the network commands. You need to do an ATRE to restore the radios firmware settings to defaults.

The FR is a software command to perform a triggering of the Reset Line (power cycle). It does not change commands that have been written to flash.

So i think it’s better to use power cycle reset since it actually just reset the XBee. One more question, is it possible to get the current watchdog timer value? I mean like many seconds/minutes has passed since the last contact with the PAN coordinator. Is it possible? Thank you.

What exactly is it you are trying to achieve? Doing an FR will not cause a router to leave a network nor will doing a reset on the reset line. For that you must issue a Network Reset (ATNR (1 or 0)).

Ah my bad. But i thought that a router will always search new coordinator on every power cycle.
The scenario is:
I have a sensor node that constantly moving between two coordinator (that upload the data to internet via microprocessor) and i need (almost) real-time data from the sensor node. The distance between the coordinator is two kilometers away and can be traveled under 3 minutes. So there is a time where the sensor node is leaving a coordinator radius and entering a new one’s. And i have to wait 3 minutes until the sensor node leave the old network and join the new one and finally get a new data from it. Is it clear enough? Thank you very much.

You are using the wrong product for this type of application. For this, I would use the XBee 802.15.4 modules instead. Then I would just simply Clone your base module. By doing this, your 3rd module that is moving can send data to either point that is in range without needing to Associate or Just. It just simply needs to be in range of one of the two modules.

So only XBee S1 (802.15.4) is suitable for this application? Is there any work around so XBee S2 can do this type of application? Thank you

No, there really is no way to make the Zigbee enabled modules do this. really the point to point/multi-point products work best with this type of application.

ahh how unfortunate i am. Okay thanks for the discussion. That really answer my question. Thank you very much.