Hi,
I am planning a simple zigbee network with 1 coordinator and 3 end-point.
I use Digi Xbee Znet 2.5 modules.
Initially I need to send 2-byte data every 30 seconds, from each end-point to the coordinator.
Currently, I am working with 1 coordinator and 1 end-point. I use transparent mode now. And the coordinator is receiving what is sent by the end-point.
My question is, when the coordinator receives a byte how will it identify where did it come from, if more than 1 end-point is running on the network ?
(Each wireless module is controlled by a PIC18 uC.)
I can speak to the series 1 modules (series 2.5 use Ember’s chips and normally, ZigBee, whereas series 1 are bare 802.15.4 or use DigiMesh). ZigBee is the network layer protocol OPTION for 802.15.4 modules, needed only if you intend to have multi-hop mesh networks.
Answering your question: Yes, at the 802.15.4 layer, every MAC layer frame has a source and destination MAC address, much like ethernet 802.3. If you work with the correct protocol layer and programming interface, you can know the source address. With simple 802.15.4 mode (no ZigBee), you can if you wish do peer to peer networking, where any node can send data to any other (in range) node by knowing the node’s address. Or a node can do a broadcast, as in 802.3, and all in-range nodes will get the data frame.
So, the elegance of meshing makes sense if you must use hopping. Via ZigBee or better, DigiMesh. But for simple networks, even peer to peer wireless is easy, and there’s no need for a PAN Coordinator.
Look at the XBee “AT registers” - you can set the desired destination MAC address and get the source address for the last packet. Better, use the Digi Binary API - no need to use AT commands after startup.