NCS(1.3.2) nRF Desktop cannot connect with Zephyr SW LL.

RE: NCS(1.3.2) nRF Desktop cannot connect with Zephyr SW LL.

Einar Thorsrud — Sat, 17 Oct 2020 09:29:33 GMT

Hi,

This seems to be a tight fit. I was able to to make it build by reducing CONFIG_USB_NRFX_EVT_QUEUE_SIZE. You can also try to reduce stack depth, mem pool size or similar, all in app_Zrelease.conf. I have not verified what changes are safe or not though.

RE: NCS(1.3.2) nRF Desktop cannot connect with Zephyr SW LL.

helen — Fri, 16 Oct 2020 09:45:43 GMT

Hi，

I modify the configuration of nrf52820dongle_nrf52820\app_ZRelease.conf

#CONFIG_BT_LL_SW_SPLIT=y
CONFIG_BT_LL_NRFXLIB=y

Compile error, suggesting that there is no libble_controller_.a,

I am in the path of nrfxlib\ble_controller\lib\cortex-m4\soft-float Copy libble_controller_s140.a and
rename it to libble_controller_.a.

Error after compiling again, the prompt: region `SRAM' overflowed by 3313 bytes

How should I choose s140 correctly?

How should I configure so that the RAM of 52820 can support S140?

RE: NCS(1.3.2) nRF Desktop cannot connect with Zephyr SW LL.

Einar Thorsrud — Thu, 15 Oct 2020 12:26:06 GMT

Hi,

There are a few things to consider here. Low Latency Packet Mode (LLPM) is only supported by the SoftDevice LL, and not by the Zephyr LL, as you can see here. Also, LLPM is only supported by S132 and S140, and of those only S140 supports nRF52820, as you can see here.

Therefore it is expected that using Zephyr LL on the dongle does not work, and your only option is to use S140. Is the problem that you are not able to make it fit in RAM? Is that also the case if you don't make a debug build?