Different feature sets description?

Hi.

Where could I find a description about each feature-set firmware one can flash on XBP-24 XBee module?

I can easily understand what to expect from “standard” firmwares, but what about ZIGBEE ROUTER/END DEVICE DIGITAL IO or differences between ZIGBEE ROUTER API and ZIGBEE ROUTER SENSOR, for example?

Thanks!

ZigBee Router AT means the moduel works in Transparent mode and you can issue AT commands for communication with other modules.
ZigBee Router API means the module works in API mode and you need to API frames for communication between the modules.