User's Manual

25 ProBee-ZE20S Series User Guide Rev.0.1
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.
3.5 ZigBee Security
Security is a major concern in the ZigBee architecture. Although ZigBee uses the basic security elements
in IEEE 802.15.4 (e.g., AES encryption & CCM security modes), the ZE20S increase the security level
with:
• 128 bit AES encryption algorithms
• Strong, NIST-approved security
• Defined Key Types (Link, Network)
• Defined Key setup and maintenance
• CCM (Unified/Simpler mode of operation)
• Trust Centers
Poll Request
Data Exchange
Parent Node
Sleepy End Device
Sleep Wake-Up
Sleep
S53
S52
S54