Vimar 03925, Руководство по установке

Страница: 10 / 26

10
4.6 Payload
The payload of data telegrams is 13 … 17 bytes long (depending on the size of the Optional Data field) and consists of the following fields:
■
Length (1 byte)
The Length field specifies the combined length of the following fields. The content of the field depends on the size of the Optional Data field (which can be 0 / 1 / 2
or 4 byte). The resulting Length setting would be 12 / 13 / 14 or 16 byte (0x0C / 0x0D / 0x0E / 0x10) respectively.
■
Type (1 byte)
The Type field identifies the data type used for this telegram. For 03925 data telegrams, this field is always set to 0xFF to designate manufacturer-specific data field.
■
Manufacturer ID (2 byte)
The Manufacturer ID field is used to identify the manufacturer of BLE devices based on assigned numbers. Vimar has been assigned 0x03DA as manufacturer ID
code. The Manufacturer ID can be changed via the NFC configuration interface as described in chapter 6.7.5.
■
Sequence Counter (4 byte)
The Sequence Counter is a continuously incrementing counter used for security processing. It is initialized to 0 at the time of production and incremented for each
telegram (data telegram or commissioning telegram) sent.
■
Switch Status (1 byte)
The Switch Status field reports the button action. The encoding of this field is described in chapter 4.7.
■
Optional Data (0 / 1 / 2 or 4 byte)
03925 provides the option to transmit additional user-defined data within each data telegram. This data can be used to identify user-specific properties. The length
of the Optional Data field is defined in the Configuration register as described in chapter 6.7.7.
■
Security Signature (4 byte)
The Security Signature is used to authenticate 03925 radio telegrams as described in chapter 4.8.
Figure 13 below illustrates the data telegram payload.
0x0C
…
0x10
0xFF
Manufacturer ID
0x03DA
Sequence Counter
(4 Byte)
Switch
Status
Optional Data
(0/1/2/4 Byte)
Security Signature
(4 Byte)
LEN TYPE
4.7 Switch status encoding
The Switch Status field within the Payload data identifies the 03925 action (button push or release). 03925 uses the following sequence to identify and transmit but-
ton contact status:
1. Determine direction of the energy bar movement (Push Action or Release Action)
2. Read input status of all button contacts
3. Calculate data payload
4. Calculate security signature
In 03925, the type of action (Press Action or Release Action) is indicated by Bit 0 (Energy Bar). If a button contact has been actuated during Press Action or Release
Action then this is indicated by the according status bit set to ‘1’.
Note that all contacts that were pressed during Press Action will be released during Release Action. The case of continuing to hold one (or several) button contacts
during Release Action is mechanically not possible.
The switch status encoding used by 03925 is shown Figure 14 in below.
Switch Status
Reserved B1 B0 A1 A0
ACTION
TYPE
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Shal be 0b000
0 = No Action
1 = Action 0 = No Action
1 = Action 0 = No Action
1 = Action 0 = No Action
1 = Action 0 = Release Action
1 = Press Action
4.8 03925 telegram authentication
03925 implements telegram authentication to ensure that only telegrams from senders using a previously exchanged security key will be accepted. Authentication
relies on a 32 bit telegram signature which is calculated as shown in Figure 15 below and exchanged as part of the radio telegram.
Telegram format
Figure 13 – Data telegram payload structure
Figure 14 – 03925 button action encoding