USER MANUAL
PTM 216Z – 2.4 GHz Zigbee Generic Switch Pushbutton Transmitter Module
© 2018 EnOcean | www.enocean.com
F-710-017, V1.0
PTM 216Z User Manual | v1.2 | November 2018 | Page 11/43
3.2
Telegram structure
PTM 216Z transmits radio telegrams in the 2.4 GHz band according to the IEEE 802.15.4
frame structure using a Zigbee Green Power compliant payload.
Note that the byte order used by these standards is little endian. This means that for multi-
byte structures (such as 2 byte, 4 byte or 8 byte fields) the least significant byte (LSB) is
transmitted first.
The frame structure used by PTM 216Z consists of the following four main parts:
PHY Header
The PHY header indicates to the receiver the start of a transmission and provides infor-
mation about the length of the transmission.
It contains the following fields:
-
Preamble
Pre-defined sequence (4 byte, value
0x00000000)
used to adjust the receiver
to the transmission of the sender
-
Start of frame
Pre-defined symbol (1 byte, value
0xA7
) identifying the start of the actual da-
ta frame
-
Length of frame
1 byte indicating the combined length of all following fields
MAC Header
The MAC header provides detailed information about the frame.
It contains the following fields:
-
Frame control field
2 bytes (always
0x0801
) which identify frame type, protocol version, ad-
dressing and security mode
-
Sequence number
1 byte sequential number to identify the order of transmitted frames
-
Address
PAN ID and address of source (if present) and destination of the telegram
PTM 216Z does not use source address and source PAN ID
MAC Payload
The MAC payload is based on the Zigbee Green Power standard. It contains telegram
control, device ID, telegram data and telegram security fields.
MAC Trailer
The MAC Trailer contains the Frame Check Sum (FCS) field used to verify the integrity of
the telegram data.
