Restardting the advertisement on nRF52840-DK

RE: Restardting the advertisement on nRF52840-DK

Vidar Berg — Tue, 25 Jul 2023 10:57:22 GMT

The BLE host APIs are the same regardless of what controller you use. This is why you can use the Softdevice controller with the Zephyr samples as well.

You can find the Kconfig symbols for the Softdevice controller here: https://github.com/nrfconnect/sdk-nrf/blob/main/subsys/bluetooth/controller/Kconfig

RE: Restardting the advertisement on nRF52840-DK

ujur007 — Tue, 25 Jul 2023 10:19:50 GMT

[quote userid="4240" url="~/f/nordic-q-a/102087/restardting-the-advertisement-on-nrf52840-dk/438036"]The Softdevice controller is selected by default in all BT samples, including those in the Zephyr repo, if you are using the nRF Connect SDK. [/quote]

Ok. I think, I did not understand which controller is used by default from the following webpage the last section mentions it.

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/protocols/ble/index.html

Also, can you tell what difference it will make in BLE API's if I am using either controller? I have just migrated the application from Zephyr to nRF connect SDK Zephyr.

Above Kconfig options are too much for me, if you have some advance feature's documentation, do let me know.

RE: Restardting the advertisement on nRF52840-DK

Vidar Berg — Tue, 25 Jul 2023 10:12:00 GMT

Sorry, I just assumed you didn't have CONFIG_BT_CENTRAL enabled. With the central role enabled, you also need to increase CONFIG_BT_CTLR_SDC_PERIPHERAL_COUNT as it defaults to '1' when CONFIG_BT_CENTRAL=y. However, you must leave at least one connection to the central. So if CONFIG_BT_MAX_CONN=10, the most you can set CONFIG_BT_CTLR_SDC_PERIPHERAL_COUNT to is '9'.

The Softdevice controller is selected by default in all BT samples, including those in the Zephyr repo, if you are using the nRF Connect SDK.

RE: Restardting the advertisement on nRF52840-DK

ujur007 — Mon, 24 Jul 2023 17:57:52 GMT

I think the problem is solved. I have some questions.

I am not using Nordic Softdevice controller. As most of the samples by default use Zephyr BLE controller..

Also, CONFIG_BT_CTLR_SDC_PERIPHERAL_COUNT was set to 1. When I put that in my prj.confing and set it to 10, I got error stating

/ncs/v2.0.0/zephyr/include/zephyr/toolchain/gcc.h:77:36: error: static assertion failed: ""
   77 | #define BUILD_ASSERT(EXPR, MSG...) _Static_assert(EXPR, "" MSG)
      |                                    ^~~~~~~~~~~~~~
/home/ujjval/ncs/v2.0.0/nrf/subsys/bluetooth/controller/hci_driver.c:51:1: note: in expansion of macro 'BUILD_ASSERT'
   51 | BUILD_ASSERT(!IS_ENABLED(CONFIG_BT_CENTRAL) ||

Then I commented the line CONFIG_BT_CENTRAL=y, that solved this error.

I can't use both central and peripheral at once when I want to turn on multiple connections right?

I am not sure the following two options also may have solved the error.

CONFIG_BT_MAX_CONN=10
CONFIG_BT_MAX_SCO_CONN=10

Or the above mentioned...

CONFIG_BT_CTLR_SDC_PERIPHERAL_COUNT=10

RE: Restardting the advertisement on nRF52840-DK

Vidar Berg — Mon, 24 Jul 2023 06:58:32 GMT

Please check what the CONFIG_BT_CTLR_SDC_PERIPHERAL_COUNT symbol is set to in your generated ".config" file.

This symbol says how many peripheral links the Softdevice controller is configured to support.

[quote user="ujur007"]BTW, I have disabled some of the peripherals/gpio's for low-power application. I hope that has nothing to do with the above error.[/quote]

Thanks, but this should not affect the BT stack configuration.

RE: Restardting the advertisement on nRF52840-DK

ujur007 — Sat, 22 Jul 2023 08:16:27 GMT

I have make changes to proj.conf and added

CONFIG_BT_MAX_CONN=10

still, I get the above error.

BTW, I have disabled some of the peripherals/gpio's for low-power application. I hope that has nothing to do with the above error.

RE: Restardting the advertisement on nRF52840-DK

Vidar Berg — Fri, 21 Jul 2023 11:27:33 GMT

Hello,

The error is CONNECTION LIMIT EXCEEDED (0x9) because you are attempting to start connectable advertising while you are in a connection. If you want to support more connections, you can increase the CONFIG_BT_MAX_CONN value in your prj.conf file.

Best regards,

Vidar