USER MANUAL PREVIEW
PTM 535BZ
–
BLUETOOTH AND ZIGBEE GREEN POWER PUSHBUTTON TRANSMITTER
© 2021 EnOcean | www.enocean.com
F-710-017, V1.0
PTM 535BZ User Manual | v1.0 | May 2021 | Page 17/112
3.3
Telegram format
PTM 535BZ transmits Bluetooth Low Energy (BLE) radio telegrams in the 2.4 GHz band. This
chapter provides a summary of the BLE frame structure; for detailed information please refer
below summarizes the high-level BLE frame structure. The content of these
fields is described in more detail below.
Figure 7
–
BLE frame structure
3.3.1
Byte order
BLE uses little endian location meaning that if a data structure (e.g. Access Address, Header
or Source Address) is bigger than one byte then the least significant byte is transmitted first.
Considering for instance the case of the four-byte Access Address
0x8E89BED6
, these 4 bytes
will be transmitted (and received) in the order
0xD6
first,
0xBE
second,
0x89
third and
0x8E
last.
3.3.2
Preamble
The BLE Preamble is 1 byte long and identifies the start of the BLE frame. The value of the
BLE Preamble is always set to
0xAA
.
3.3.3
Access Address
The four-byte BLE Access Address identifies the radio telegram type. For advertising frames,
the value of the Access Address is always set to
0x8E89BED6
.
3.3.4
Advertising PDU Header
The Advertising PDU Header identifies certain radio telegram parameters.
below
shows the structure of the Advertising PDU header. The Advertising PDU Header is set to
0x1342
for data telegrams and
0x2442
for commissioning telegrams.
Figure 8
–
Advertising PDU header structure