Vimar 03925, Руководство по установке

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8
Telegram format
4. Telegram format
03925 transmits Bluetooth technology Low Energy (BLE) radio telegrams in the 2.4 GHz band. For detailed information about the Bluetooth technology Low Energy
standard, please refer to the applicable specifications.
Figure 8 below summarizes the BLE frame structure.
Preamble
0xAA
Access Address
0x8E89BED6
Header
(2 Byte)
Source Address
(6 Byte)
Payload
(0 … 31 Byte)
Check Sum
(3 Byte)
The content of these fields is described in more detail below.
4.1 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.
4.2 Access Address
The 4 byte BLE Access Address identifies the radio telegram type. For advertising frames, the value of the Access Address is always set to 0x8E89BED6.
4.3 Header
The BLE Header identifies certain radio telegram parameters. Figure 9 below shows the structure of the BLE header.
Bit 15 (MSb) Bit 0 (LSb)
UNUSED
(2 Bit)
LENGTH
(6 Bit)
RX ADDR
(1 Bit)
TX ADDR
(1 Bit)
UNUSED
(2 Bit)
TYPE
(4 Bit)
00
Length of
A Payload
0: Not used 1: Random 00
0010: TX-only Advertising
(ADV_NONCONN_IND)
4.4 Source address
The 6 byte BLE Source Address (MAC address) uniquely identifies each 03925 product.
03925 supports two source address modes:
■
Static Source Address mode (default) In this mode, the source address is constant (but its lower 32 bit can be configured via NFC interface)
■
Private Resolvable Address mode (NFC configurable) In this mode, the source address changes for each transmission
03925 uses by default Static Source Address mode.
Private Resolvable Address mode can be selected by setting the Private Source Address flag in the Configuration register (see chapter 6.7.7) to 0b0.
These two address modes are described in the following chapters.
4.4.1 Static source address mode
By default, 03925 uses static source addresses meaning that the source address is constant during normal operation. The static source address can be read
and configured (written) via NFC as described in chapter 6.
The structure of 03925 static addresses is as follows:
■
The upper 2 bytes of the source address are used to identify the device type and set to 0xE215 for all 03925 devices. These two bytes cannot be changed.
■
The lower 4 bytes are uniquely assigned to each device. They can be changed using the NFC configuration interface as described in chapter 6.7.3
Figure 10 below illustrates the static address structure used by 03925.
Product Type ID (16 Bit)
Unique Device Address (32 Bit)
0xE215
MSB LSB
Figure 8 – Default radio transmission sequence
Figure 9 – BLE header structure
Figure 10 – BLE static source address structure