In a ZigBee network, routers and end devices must discover and join a network before they can communicate with other ZigBee devices. The XBee ZB firmware includes a number of AT commands that can be used to configure the ZigBee joining parameters (i.e. scan channels, PAN ID, permit join, security settings, etc). See the XBee ZB product manual for details on the joining process and related AT commands.
When becoming familiar with the concept of joining in ZigBee, there are a number of factors that determine which network(s) a device can join. When an XBee fails to join a desired ZigBee network, the AI command can be used to determine the reason the join attempt failed. This application note provides guidance on how to resolve joining problems based on the information contained in the AI command value.