Vary RSSI with Zephyr

[EricC]

Hello Nordic Team,  a broad question and not sure if this is in the realm of possibility.

I have a test environment with a test client (python/pygatt)  running on Linux with Zephyr on a 52840 board receiving streamed data from a Nordic based device. I would like to see how the Nordic device behaves in cases where the signal strength varies and would like to simulate this programmatically from the test client. Is it possible to send a command to the 52840 saying set the signal strength to a different value? In general, what are good practices and techniques for testing with varying signal strengths (and environments with interference)?

thanks in advance,

Eric

[Øyvind]

Hi Eric,

Is it possible to send a command to the 52840 saying set the signal strength to a different value?

Can this sample be something you are looking for: 
https://docs.zephyrproject.org/latest/samples/bluetooth/hci_pwr_ctrl/README.html

Kind regards,
Øyvind 

[EricC]

Oyvind, thank for your helpful and timely reply. To expand, I am running the HCI uart code on the 52840. My grasp of the concepts is a little fuzzy at this point but is it fair to say that the board supports power level changes and I just need to figure out to get an HCI command from pygatt to gatttool to bluez which will then send it to the board which will do the right thing (assuming that is possible)?

thanks in advance,

Eric

[Øyvind]

Hi Eric, 

Sorry, our resources on this topic are a little limited due to ongoing summer vacations, and those who are here are not familiar with BlueZ. However, I was able to get some suggestions using hcitool. 

cmd<ogf> <ocf> [parameters]
	Submit an arbitrary HCI command to local device. ogf, ocf and parameters are hexadecimal bytes.

OGF=0x3F

OCF=0x000E

Parameters are specified here, for example:

https://github.com/nrfconnect/sdk-nrfxlib/blob/master/ble_controller/include/ble_controller_hci_vs.h#L200

and in the original Zephyr vendor-specific HCI interface:

https://github.com/zephyrproject-rtos/zephyr/blob/master/include/bluetooth/hci_vs.h#L160

[EricC]

thanks!