This is my first post, so excuse me if I’m posting in the wrong place, and kindly let me know where I should actually post this.
First of all a brief description of what I want to do :
I am making an independent portable device that would be able to transmit and receive from many other devices such as itself. That is it should broadcast some message within a given period of time. This device will mainly consist of a PIC MCU and an XBEE module for wireless transmission.
The problem that i’m facing is that, in order to make communication as I have described above, the device should be able to switch between a Coordinator and an end device. Can someone please advice me if this is possible with the xbee modules, and how i can actually achieve this.
The Smart Energy forum is probably not the right place for this question. If you already have units, I’m assuming these are already ZigBee devices? The benefit of ZigBee being the ability to create a mesh network. Is meshing a requirement?
The ability to broadcast a message to all devices and receive a message from all devices isn’t unique to ZiBee and can be accomplished with several other XBee products, which may be more simple to build your network around.
A little more clarification on how your network should operate may help us suggest the appropriate product for you.
That being said, you can still do this in ZigBee if you wish. The difference is that you can’t switch between Coordinator and End Device on a whim. You could however, switch between end device and router if you wish, or use the collector node as a router instead of the coordinator. In ZigBee any node can still communicate to and receive information from any other node in the network.
Here is a little more detail on how our unit is expected to perform:
It is a potable device, and it should continously transmit a specific message to all the other devices within the range.
At the same time, it should be able to receive the incoming transmissions from the other devices.
After some computation, the device should be able to select a single device out of all the other devices within the range and perform a point to point communication with that device. At this point (i.e. at the selection of a specific device) it should stop sending any more broadcasts and receipts of any messages from other devices and only perform communication with that specific device.
This is basically how our device’s communication part must function.
We still have not really purchased the x-bee modules, therefore we welcome any suggestions of any other product that may enable us to perform the tasks mentioned above.
Most any of the XBee protocols should be able to handle this type of communication. All the modules are all transceivers, so bi-directional communication isn’t a problem, and there is no need to switch between coordinator and end device.
The sending of the broadcast messages and switching between addresses can all be done with your MCU sending messages to the radio to change the address it is set to send messages to. you can set up your unicast and broadcast messages in the addressing of the radios regardless of the wireless protocol you select using the XBee.
The protocol you choose may be more determined on the network topology you need. If meshing not necessary, I would recommend the XBee 802.15.4 modules. If meshing is required, then either the ZigBee or DigiMesh modules are necessary. The selection of which, might be based on what sleep functionality you intend to use, or other requirements on how your network should operate.