@eric, is it possible to wake up DK from Gateway and send data to DK?
The DK must stay connected to the gateway in order to receive any notifications from it. So there isn’t any way to have a DK go to deep sleep and then wake up somehow upon a signal rom a gateway as the radio on the DK would be turned off.
There are two options. You can keep the DK connected and make sure you are using SLEEP_MODE_CPU and all peripherals are turned off. There are some new power-saving tricks in v2.0.50 as well, such as reducing the radio power and configuring longer gateway connection intervals. These should help you increase battery life, but the DK will always stay connected and can receive data at any time.
The second is to turn off the radio on bluz and only turn it back on after certain timing intervals. So you can turn off the radio, then every 5 minutes turn it on, get connected, and send/receive data before turning it off again. If the window is too short, then the time spent connecting would negate any power savings. If you wanted data sent every hour, this may work. If you wanted it sent every minute, it wouldn’t work so well.