generall question about the xbee

I want to build a network with about 100 endnodes over 3 floors.
Because of some heavy steel in the ceiling i assume i need
a router for every floor to reach all nodes.
I have one PC to send/receive the commands from/to all nodes.
All my applications behind the endnodes have a unique ID.
I need to send/receive only 10 bytes(a simple ASCII string)
as command/answer.
Two questions.

  1. what kind of network and xbee modules would you suggest?
  2. If i want to send a string to a endnode i need to change the
    low/high address. I guess in AT mode it takes at least >1 second
    to change because of the Guard Times.
    Is this correct?

Please help me to find answers. Many thx.

I suggest the Xbee series 2 (aka. Xbee ZB) or the Xbee series 1 implementing Digimesh. I assume cost is a factor so I would not go with the Pro version since you should be well within range of a router since you are in a building. Next question is how many of these nodes will be battery powered? As for the number and placement of routers depends on the building structure/layout, the distances you will be transmitting, and how reliably you want to caputre the data. Also you can only have so many nodes attached to a router. I believe that number is 12 but you can call Digi if that is a factor. As for sending data to end nodes, API format would be the fastest way since you put the destination in API packet. If you still want to use AT mode, change the gaurd time to a small number, like 3, and that will change the wait period from 1 second to about 3 milliseconds.

Yes, I’d recommend a ZNet 2.5 PAN (aka Series 2), to eventually be migrated to ZB (requires a simple firmware upgrade of the modules).

Due to the number of modules involved, and being spread over 3 floors, he’d want some sort of mesh network rather than point-to-multipoint (802.15.4) in my opinion. End nodes could then associate to routers, and the node limit of the CP-X gateway won’t be reached.

Thank you. This helps alot.
Actually i´m not sure how to use the API.

I wasn´t able to find “good” examples.
First i will try to decrease the gaurd time as suggested and use AT commands.

If it´s to slow i guess i have to face API. :slight_smile: