Multiple EMX in one project

Hi Guys,

I have a project that requires a main controller and slave controller type of topology. I also need to be able to send commands to each slave individually. Ideally it would need to be wireless as well.

I know I could use Xbee and have a mesh, but how would I send commands to just a single slave controller?

I’m open to other suggestions of wireless technology but would also like to keep the overall cost of the slave units down. The distance will only be up to 10 meters at most. I would think the maximum number of slave controllers wouldn’t exceed 15 either, but would like to future proof it as well.

Thanks in advance!

You could simply include a “header” in the information you send between the devices, and discard the command if it doesn’t apply to a specific node. Kind of like a MAC address for a local ethernet broadcast, it identifies the device you’re trying to target. Since you mention 15 devices, you can get away with only a 5-bit address, but to future proof it make it 8 and you get a lot more :slight_smile:

You could use an EMX for your main controller and possibly USBizis for slaves, checkout the Nordic wireless chip.

http://www.tinyclr.com/forum/1/3438/

I need the slaves to be basically un-configurable for the end user, like a plug an play device. Would using the header type arrangement be able to set the ID for connecting devices programatically through ZigBee?