USER MANUAL
TCM 515Z – 2.4 GHZ IEEE 802.15.4 Transceiver
© 2017 EnOcean | www.enocean.com
F-710-017, V1.0
TCM 515Z User Manual | v1.6 | September 2017 | Page 30/46
Appendix A
IEEE 802.15.4 Frame Structure
A.1
IEEE 802.15.4 High Level Frame Structure
TCM 515Z transmits and receives radio telegrams in the 2.4 GHz band according to IEEE
802.15.4 frame structure. The external host is responsible for the proper decoding of re-
ceived telegrams and proper encoding of telegrams to be transmitted.
The following information about the IEEE 802.15.4 standard and its implementation in PTM
215ZE and PTM 515Z is given for reference only. Please refer to the applicable documents
for detailed information.
Note that the data format 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 IEEE 802.15.4 frame structure consists of the following four main parts:
PHY Header
The PHY header indicates to the receiver the start of a transmission and provides in-
formation about the length of the transmission.
It contains the following fields:
o
Preamble
Pre-defined sequence (4 byte, value 0x00000000) used to adjust the receiver
to the transmission of the sender
o
Start of frame
Pre-defined symbol (1 byte, value 0xA7) identifying the start of the actual
data frame
o
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:
o
Frame control field
2 bytes to identify frame type, protocol version, addressing and security
mode
o
Sequence number
1 byte sequential number to identify the order of transmitted frames
o
Address
PAN ID and address of source (if present) and destination of the telegram
EnOcean PTM 535Z and PTM 215ZE do not use source address and source
PAN ID (the EnOcean ID is part of the payload).
MAC Payload
The MAC Payload field contains telegram control, device ID, telegram data and tele-
gram security (if present) fields.
The MAC Payload field structure depends on telegram type (data or commissioning)
and security mode (secure or standard transmission).
