Hi Barry,
> I attempting to get the advertising data from a commercially available
> sensor device using the DBus API.
> The sensor device gives different manufacturer data depending if the
> event type is ADV_IND or SCAN_RSP, as you can see below in the btmon
> output.
>
> With DBus I am subscribing to the InterfacesAdded signal which
> triggers when the device has been found. However, it only seems to
> give me the information for the SCAN_RSP.
> If I subscribe to the PropertiesChanged signal on the device, that is
> also only giving the data from the SCAN_RSP event.
>
> How do I access both types of data with the DBus API?
>
> Thanks,
> Barry
>
> $ bluetoothctl -v
> bluetoothctl: 5.50
>
>
> btmon output for sensor device:
>
>> HCI Event: LE Meta Event (0x3e) plen 43 #1969 [hci0] 740.157687
> LE Advertising Report (0x02)
> Num reports: 1
> Event type: Connectable undirected - ADV_IND (0x00)
> Address type: Random (0x01)
> Address: DC:76:F7:E1:62:E0 (Static)
> Data length: 31
> Flags: 0x06
> LE General Discoverable Mode
> BR/EDR Not Supported
> Company: Blue Maestro Limited (307)
> Data: 1b640e10010400e701a527f50100
> Name (complete): DC76F7E1
> RSSI: -44 dBm (0xd4)
>> HCI Event: LE Meta Event (0x3e) plen 41 #1970 [hci0] 740.158684
> LE Advertising Report (0x02)
> Num reports: 1
> Event type: Scan response - SCAN_RSP (0x04)
> Address type: Random (0x01)
> Address: DC:76:F7:E1:62:E0 (Static)
> Data length: 29
> Company: Blue Maestro Limited (307)
> Data: 27fd27f227ea0000010201b600e4017100f4018c0000000000
> RSSI: -44 dBm (0xd4)
> @ MGMT Event: Device Found (0x0012) plen 74
> {0x0002} [hci0] 740.158704
> LE Address: DC:76:F7:E1:62:E0 (Static)
> RSSI: -44 dBm (0xd4)
> Flags: 0x00000000
> Data length: 60
> Flags: 0x06
> LE General Discoverable Mode
> BR/EDR Not Supported
> Company: Blue Maestro Limited (307)
> Data: 1b640e10010400e701a527f50100
> Name (complete): DC76F7E1
> Company: Blue Maestro Limited (307)
> Data: 27fd27f227ea0000010201b600e4017100f4018c0000000000
> @ MGMT Event: Device Found (0x0012) plen 74
> {0x0001} [hci0] 740.158704
> LE Address: DC:76:F7:E1:62:E0 (Static)
> RSSI: -44 dBm (0xd4)
> Flags: 0x00000000
> Data length: 60
> Flags: 0x06
> LE General Discoverable Mode
> BR/EDR Not Supported
> Company: Blue Maestro Limited (307)
> Data: 1b640e10010400e701a527f50100
> Name (complete): DC76F7E1
> Company: Blue Maestro Limited (307)
> Data: 27fd27f227ea0000010201b600e4017100f4018c0000000000
>
>
> Device information from the InterfacesAdded DBus signal:
>
> {'Adapter': '/org/bluez/hci0',
> 'Address': 'DC:76:F7:E1:62:E0',
> 'AddressType': 'random',
> 'Alias': 'DC76F7E1',
> 'Blocked': False,
> 'Connected': False,
> 'LegacyPairing': False,
> 'ManufacturerData': {307: [39, 253, 39, 242, 39, 234, 0, 0, 1, 2, 1,
> 182, 0, 228, 1, 113, 0, 244,1, 140, 0, 0, 0, 0, 0]},
> 'Name': 'DC76F7E1',
> 'Paired': False,
> 'RSSI': -51,
> 'ServicesResolved': False,
> 'Trusted': False,
> 'UUIDs': []}
>
> Looking at the propertiesChanged signal on the device, it is also only
> showing the same manufacturer data:
> org.bluez.Device1 {'RSSI': -45, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
> org.bluez.Device1 {'RSSI': -52, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
> org.bluez.Device1 {'RSSI': -54, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
> org.bluez.Device1 {'RSSI': -45, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
> org.bluez.Device1 {'RSSI': -54, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
> org.bluez.Device1 {'RSSI': -52, 'ManufacturerData': {307: [39, 253,
> 39, 242, 39, 234, 0, 0, 1, 2, 1, 182, 0, 228, 1, 113, 0, 244, 1, 140,
> 0, 0, 0, 0, 0]}} []
this is nasty from the device. So the MGMT event should return the combined data from ADV_IND and SCAN_RSP and as you see we just concat that information coming from the kernel. However when it goes out via D-Bus, it actually gets overwritten and only one is provided.
Now the question is how we represent the same manufacturer data coming once from ADV_IND and second from SCAN_RSP via the D-Bus API. You need to have a look into doc/device-api.txt and the code in src/device.c on how we handle this.
Regards
Marcel
