cancel
Showing results for 
Search instead for 
Did you mean: 

Smart Bluetooth

Anonymous
Not applicable

I am trying to get rssi value from wiced sense.

I am using raspberry pi with a ble dongle. I use bluez and gattool to connect and read data from the sense.
I have a python script reading the sensor data. However I would like to get rssi also. I tried to do hcidump, but rssi doesnt show up on the dump  I checked the advertisement packet format and it says the flag for rssi is 0xA ( is rssi same as tx power level here? I am not familiar with physical layer terms).

I used gattool to connect to the sense and dumped the raw data. Can you please tell me which packet has data I can get rssi from?

HCI sniffer - Bluetooth packet analyzer ver 5.30

device: hci0 snap_len: 1500 filter: 0xffffffff

< 01 0D 20 19 60 00 30 00 00 00 A2 19 17 6A 73 20 00 28 00 38

  00 00 00 2A 00 00 00 00 00

> 04 0F 04 00 01 0D 20

> 04 3E 13 01 00 48 00 00 00 A2 19 17 6A 73 20 38 00 00 00 2A

  00 00

> 02 48 20 10 00 0C 00 05 00 12 01 08 00 40 00 60 00 00 00 F4

  01

< 02 48 00 0A 00 06 00 05 00 13 01 02 00 00 00

< 01 13 20 0E 48 00 40 00 60 00 00 00 F4 01 00 00 00 00

> 02 48 20 06 00 02 00 06 00 0B 01

< 02 48 00 06 00 02 00 06 00 05 05

> 04 0F 04 00 01 13 20

> 04 13 05 01 48 00 01 00

> 04 13 05 01 48 00 01 00

> 04 3E 0A 03 00 48 00 60 00 00 00 F4 01

0 Likes
1 Solution
Anonymous
Not applicable

The TX power is part of ADV Packet and is used in association with the Client Receive Event as shown below

22:37.907  com1   <e  LE Event                                                 

LE_Event_Code: LE Advertising Report Event

                

HCI Event

          

com1@115200nfc

    [3E 21]:

    02 01 00 00 11 11 11 11 11 01 15 02 01 06 11 07 33 8D C2 86 0C C3 EB B0 E9 40 F4 CB E8 60 B2 F9 A5

    event = 0x3E (62, "LE Event")

    LE_Event_Code = 0x2 (2, "LE Advertising Report Event")

    Num_Reports = 0x1 (1)

    Event_Type[0] = 0x0 (0, "Connectable Undirected Event")

    Address_Type[0] = 0x0 (0, "Public Address")

    Address[0] = "011111111111"

    Data_Len[0] = 0x15 (21)

    Data[0] = "02 01 06 11 07 33 8D C2 86 0C C3 EB B0 E9 40 F4 CB E8 60 B2 F9"

    RSS[0] = -91 (127 means RSSI is not available, Range from -127 to 20 dbm)

The RSSI is based on the Client Receive event which produces the event Report that contains the RSSI value.

Thanks

JT

View solution in original post

0 Likes
9 Replies
Anonymous
Not applicable

Hello sareena,

Please see the post: Re: How to find RSSI from WICED SMART?

Thanks

JT

0 Likes
BoonT_56
Employee

sta2378

Is this still an issue?

0 Likes
Anonymous
Not applicable

Hello

I haven't been able to work on this part of the project this week.

But I still don't understand how I can call this function from my python script.

I want to know if the adv packets have rssi value.

boont

jakewtorres

0 Likes
BoonT_56
Employee

I believed JT had given his thoughts on this qn in his posting above. Yes, the adv packets contain RSSI value. Please refer to his suggested reference thread for more details.

0 Likes
Anonymous
Not applicable

Hi boont Thank you for the prompt response.
I read that post.I didn't find this in bluez stack.  It is still not clear where I call this function from?

0 Likes
Anonymous
Not applicable

The TX power is part of ADV Packet and is used in association with the Client Receive Event as shown below

22:37.907  com1   <e  LE Event                                                 

LE_Event_Code: LE Advertising Report Event

                

HCI Event

          

com1@115200nfc

    [3E 21]:

    02 01 00 00 11 11 11 11 11 01 15 02 01 06 11 07 33 8D C2 86 0C C3 EB B0 E9 40 F4 CB E8 60 B2 F9 A5

    event = 0x3E (62, "LE Event")

    LE_Event_Code = 0x2 (2, "LE Advertising Report Event")

    Num_Reports = 0x1 (1)

    Event_Type[0] = 0x0 (0, "Connectable Undirected Event")

    Address_Type[0] = 0x0 (0, "Public Address")

    Address[0] = "011111111111"

    Data_Len[0] = 0x15 (21)

    Data[0] = "02 01 06 11 07 33 8D C2 86 0C C3 EB B0 E9 40 F4 CB E8 60 B2 F9"

    RSS[0] = -91 (127 means RSSI is not available, Range from -127 to 20 dbm)

The RSSI is based on the Client Receive event which produces the event Report that contains the RSSI value.

Thanks

JT

View solution in original post

0 Likes
BoonT_56
Employee

sta2378

jakewtorres

Any furthur clarification?

0 Likes
Anonymous
Not applicable

Thank you. Finally figured it out.

HCI Event: LE Meta Event (0x3e) plen 42

    LE Advertising Report

      ADV_IND - Connectable undirected advertising (0)

      bdaddr 20:73:6A:17:19:A2 (Public)

      Flags: 0x05

      Unknown type 0xff with 8 bytes data

      Complete local name: 'WICED Sense Kit'

      RSSI: -52

0 Likes
Anonymous
Not applicable

Great!  Glad to hear it.

JT

0 Likes