How to get the RSSI figure on Bluesmirf?

Wireless & IoT
1

Can anyone point me to how to get an RSSI figure with a bluesmirf?

Here’s the backstory:

I have a bluesmirf gold. (Hooray!) I can connect to it thru bluetooth using zterminal running on a Mac at 9600 baud (Hooray!) I can put it into command mode using $$$, and I’ve set it to never go to sleep… (Hooray!)

However, I’m trying to get at an RSSI (Recieved Signal Strength Indication) figure… (Ooooh!)

I can get the embedded help, it comes out with the following list

–startquote–

*** SET COMMANDS SA,<1,0> - AuthenticationSB, - Send BreakSC, - Service ClassSD, - Device ClassSE,<1,0> - EncryptionSF,1 - Factory DefaultsSI, - Inquiry Scan WindowSJ, - Page Scan WindowSL,<E,O,N> - ParitySM,<0-5> - Mode (0=slav,1=mstr,2=trig,3=auto,4=DTR,5=Any)SN, - NameSO, - conn/discon StatusSP, - Pin CodeSR, - Remote AddressSS, - Service NameST, - Config TimerSU, - BaudrateSW, - Sniff RateSX,<1,0> - BondingSY, - TX powerSZ, - Raw BaudrateS7,<0-1> - 7bit dataS~,<0-3> - Profile (0=SPP,1=DCE,2=DTE,3=MDMS?,<0-1> - role switchS$, - CMD mode charS@, - io port dirS&, - io port valS%, - io boot dirS^, - io boot valS, - pio(8-11) set* DISPLAY D - Basic SettingsE - Extended SettingsG - Stored settingGB - BT AddressGK - Connect StatusG& - I/O PortsV - Firmare version OTHER ***C, - ConnectF,1 - Fast ModeI,, - Device Scan InquiryK, - Kill (disconnect)L, - Link QualityP, - Pass ThruQ - Quiet (no discovery)R,1 - RebootT,<0,1> - send data in CMD modeU,,<E,O,N> - Temp Uart ChangeZ - low power sleep& - Read switches

–endquote–

but when I send it an “L” (Link Quality) it sends me a “?” as if it doesn’t understand…

when I send it an “M” (undocumented in the chip’s onboard help, but documented in “User Guide for Roving Networks Bluetooth Serial Module Command set for RN21/22/24, and RN-41 Bluetooth Modules, BluePortXP, Firefly Serial Adapter” version 4.26 dated October 19 2007 on page 10 as “display remote side modem signal status” I get a response of “8000” thru the terminal program

what is this figure? what does it mean? is is anything to do with RSSI at all? why is it not documented on-chip?

If it is not RSSI. What is? We would dearly like to find out…

Someone from spark@ said that M is in the right direction…but it only gives one constant reading of 8000.

I would really appreciate some help. It’s been a slog so far, and I’ve tried and looked everywhere.

2

wildwoman:
Can anyone point me to how to get an RSSI figure with a bluesmirf?

Looking at the specification sheet for the RN-41 Bluetooth adapter, it appears to be Bluetooth SIG 2.0 compliant, which is good since pre-1.2 devices were unable to report RSSI.

I have not used this hardware so I cannot answer definitely, however, having done lots of Bluetooth development using the Linux BlueZ stack and the Microsoft and Widcomm Bluetooth stacks for Windows, I can tell you that RSSI reporting is only accessible in the device discovery process. You may be able to retrieve a “link quality” reading for a connected session, but I do not believe you will be able to collect RSSI.

I would love it if you could prove me wrong, though I believe I am the bearer of bad news. :frowning:

-Josh