I hope you are doing great.
Just to confirm, are you waiting for some information from the parent?
In other words, the SED is sending data requests to the coordinator? What is the cluster that you are working on?
Are you working with a specific Application note?
I am doing great, hope you are too.
I am using Jn5189 as a coordinator using the control bridge application provided along the SDK. Also I am a couple of 3rd party sleepy ZigBee end devices. Some of these devices support IAS/IASWD cluster and other support ON/OFF cluster's.
My problem is I don't know the wake-up interval of these devices, so after doing some research I found that during the device's active time they are sending "Data Requests" to coordinator indicating that they are ready to receive commands/data from the coordinator.
So I want to know how can I handle "Data request" so that I will know whenever the sleepy end device is in active state.
You need to consider some points. Please look at the https://www.nxp.com/docs/en/user-guide/JN-UG-3113.pdf
B.2 Sending Data to Sleeping End Devices
The stack will handle this request and answer back setting the frame pending flag.
The device won't enter to sleep mode and it will wait for the data that the parent wants to send.
For better information please look at the next chapter B.2.1 Acknowledged Data Transmission to Sleeping End Device, you have 7 seconds after the initial transmission for the SED ack. It is important that your end devices should be synchronized with the wake-up time of your device.
However, after the join request, the parent receives the timeout. You could take this time as a reference to your device.