I have a Boron / Xenon combo and right now that seems to work fine. i.e The Xenon is connected to my mini MESH network.
Now I just want to concentrate on developing the code on the Xenon. Do I need to have my Boron powered up to do this? I won’t be sending any info to it at this early stage. I just want to setup all my peripherals etc…
New to particle 
Thanks,
J.
You can write code for the Xenon without it being ON or connected.
You just need it connected via USB or via the Boron when you want to flash your new code to it.
If you are using web IDE then set your Xenon under Devices as the target. Do a compile and download (cloud symbol next to app name). Connect the Xenon via usb and put it in DFU mode (flashing yellow). Use the CLI to usb flash to your Xenon. If you put SYSTEM_MODE(MANUAL); at the start of your code then stop the app looking for the mesh network whilst you are getting perioherals working.
Excellent!!
Thanks guys!