SparkFun Forums

[sebmadgwick]

I wish to create system where there will be many screens in a room, each with its own wireless controller. I am considering using XBee (series 1) for the task and using a different network address for each P2P pair. I doubt there would be more than 20 pairs in a room.

I wondered if anyone has any experience of this and could perhaps tell me if this could have any potential problems?

Also, is there any risk that the audience wondering in and out of the room may interfere with the system (e.g. lots of i-phone, perhaps even nearby XBee/ZigBee devices)?

[stevech]

IEEE 802.15.4, the MAC and PHY protocols, irrespective of whatever network layer you do or don't use, such as ZigBee... has no limit.
So it become a question of transmitter duty cycle - how often do nodes transmit. that's under your control.
A transmission is less than 10mSec. So there's a potential to do a lot of messaging. 802.15.4 is a CSMA/CA protocol (listen before transmitting) as is 802.11. Thus it works well to a point, where a very busy network begins to thrash.

So it's all about your choice of network layer protocol or you may choose to use none and reduce overhead traffic. And eliminate beacons.

WiFi isn't much of a problem - worst case is some WiFi streaming video. But you simply change channels on the '15.4 system.
Bluetooth is a freq. hopper - not an issue.

[sebmadgwick]

Thanks for the info. It sounds we should be OK. I will only be able to spare a couple of days to design and make these wireless controllers so I want to be happy that I don’t start in the wrong direction.