SENA ProBee-ZE20S-SEME - Manual (Page 39)

ProBee-ZE20S-SExx User Guide Rev 1.8 39
Figure 3-1 Sleep Interval and Wake-up Timing
The sleepy end-device can also wake up from the sleep mode by GPIO0 interrupt or incoming serial data.
Once it wakes up, it also polls with the parent node at S52 interval and goes into sleep mode after S54
time elapses after the last data exchange.
Note: If the sleepy end-device wakes up by incoming serial data, the integrity of the first incoming byte is
not guaranteed. It is strongly recommended to wake up the sleepy end-device by using GPIO0 first before
sending the serial data or use higher level serial data protocol to check the data integrity.
3.8 Starting Key Establishment
To communicate with other node by Smart Energy cluster command, each node is required to exchange
link keys and security data for authentication called “Key Establishment”. That process is driven by ‘Key
Establish Cluster’ and is to be taken when the Smart Energy device joins to the Trust Center(coordinator).
Key Establishment process is taken as follows:
 Coordinator forms a Smart Energy network.
 Router or end-device tries to join to the network and Trust Center(coordinator) requests the link
key for joining process.
 After all joining process is completed, Trust Center or joining node send ‘Initiate CBKE Request’
command (Key Establishment Cluster) to the other.
 The other responses ‘CBKE Response’ and they exchange link key and ephemeral data.
 Each node regenerates link key to ‘Confirm key data’ and adds others ‘Confirm key data’ to Key
Poll Request
Data Exchange
Parent Node
Sleepy End-Device
Sleep Wake-Up Sleep
S53 S52 S54