There are three onboard wireless technologies on the CCU.
- Bluetooth - Used for pairing the devices and sharing unique identifier information
- 900 Mhz Mesh - Used for long range sustained communication with the devices
- WiFi - Connecting to the internet.
When you first pair the device the Tablet is not docked with its CM. The CM has the 900Mhz antenna on it. So when you pair, your device will not know what it is or sustained communication until the tablet is docked with its CM the first time. When the CCU begins communicating with the paired device over 900Mhz, is when the device is told what profile it is and passing live value data back and forth.
So when you see 'Waiting for 900Mhz' what its really telling you is 'I dont know what I am yet, dock the tablet on the CM so I can commnuicate'