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Version 17
Safe-E-
Stop™
User Guide
3.3 Telegram Security
The transmitted telegram contains several security features.
3.3.1 System Address
Your Personal Safety System uses 32,768 unique Master Addresses, and 15 Sub Addresses per MSD (one per
each possible associated PSD).
This system address is contained in every telegram sent between the MSD and PSD. The data is considered
valid only when the address combination matches. This is a safety measure to ensure that the MSD will act only
upon its assigned PSDs.
3.3.2 CRC
The telegram is checked for integrity by the use of a 16-bit CRC. Frames containing a mismatched CRC will be
rejected.
3.3.3 Frame Counter
Each message has an embedded frame counter that changes with every data frame. This prevents frozen data
and data frame hacking.