I understand that the 802.15.4 is IEEE and “think of that like IP in the tcp/ip world” and Zigbee rides on top of that.
I just want to know (and I can’t seem to find a concise answer on this anywhere!) what are the pros and cons of znet vs zb? Can I use digital IO with zb? is there a chart somewhere? Why would I want to use the firmware that just lists 802.15.4? Do any of these work better or worse (or faster dev time or logner dev time) with an arduino/processing?
I know. A million questions. You have your strong opinions here and I’d like to hear them. If I put this post in the wrong forum, please let me know and I’ll delete/move… figured that would be better than cross-posting.
Hopefully someone comes along and points out a more detailed resource, but until then:
XBee ZB implements a newer ZigBee stack that is compliant with a more recent specification (ZigBee PRO Feature Set), whereas the ZNet 2.5 modules use an older specification. So, XBee ZB takes the place of ZNet 2.5. It supports the same sort of things, just with more features and is generally more robust all around.
The above are multi-hop/mesh which allow for multi-hop sending of data between nodes. 802.15.4 on the other hand is only point-to-multipoint. However, since it has less overhead, you might have lower and more consistent latency in 802.15.4 over XB ZB.
So overall, the ZB and 802.15.4 modules differ mainly in that one is multi-hop and the other is point-to-multipoint.
ZNet 2.5 was an interim mesh-networking release until we had full Zigbee compliance (ZB). With the advent of ZB, we now have cross-compatibility with any device using the Zigbee 2006 or Zigbee Pro featureset. ZNet 2.5 is considered obsolete, and development on the ZNet 2.5 stack is at an end as well.
Just to rephrase cpopp’s reply - 802.15.4 is strictly a line-of-sight protocol. Any Xbee which wishes to speak to another XBee MUST have clear line of sight to that XBee. None of the nodes ‘forward’ on behalf of others - this includes the Digi gateway or ‘hub’ node.
Literally, an Xbee sends a message to a specific MAC, and that MAC must be visible radio-wise directly to that XBee.
This contasts with ZigBee (or DigiMesh) where other XBee (including the gateway) will offer automatic forwarding of messages if the sender and receiver cannot see each other.
However, 802.15.4 is very deterministic & reliable sub-100msec communications is possible - unlike ZigBee where delays/jitter of up to 5 seconds is possible as nodes rediscover routes.
This is exactly what I was after. Thank you so much for the awesome replies. I’ll get ZB loaded on these 4 and start tinkering from there.
Is it possible for series-2 Znet 2.5 radio to listen tto a 802.15.4 radio? I’m having trouble with the 2.5. The parameters I need to use are:
Packetization timeout 0
I can find many of the settings in the Znet radio, but no-acks is missing and I suspect that’s why it’s not picking up the signal from the main unit.
If it’s not possible to do this, is there a firmware version for the series2 radio that is compatible with 802.15.4?