I'm using the ZigBee Control Bridge software on the JN5169 USB stick, version 1012. I want to be able receive check-in messages from devices but despite having bound to the poll control cluster, I don't receive anything. In addition, I don't see anything in the documentation about what message might come up. I'd like to have these messages for a couple of reasons. Firstly, we want it to be the heart beat for sleepy end devices and secondly, to know when we can make read requests to the device or remove it from the PAN etc.