RSSI of PCA10112 was weaker than RSSI of PC10056

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Stian Røed Hafskjold — Tue, 01 Feb 2022 08:59:38 GMT

Hi, I took over this case since Jared is on vacation.

Did you figure out how to add the nRF21540 to the NCS project? This page contains information about what you are trying to do: Working with RF front-end modules

And here is a tutorial on how to add the description to the devicetree: http://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_radio_fem.html?highlight=nrf21540#adding-support-for-nrf21540

The description can be added to a .overlay file in the project folder. The filename should be *target*.overlay, where *target* is the target you are compiling for.

Best regards,
Stian

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Thu, 06 Jan 2022 05:59:42 GMT

I found you will posted below context at nrf connect bluetooth examples which supported nrf21540dk_nrf52840.

But, I did't understand how to follow it.

Could you mind making a tutorial to teach us how to set up 21540 FEM at ncs project?

Thanks

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Thu, 06 Jan 2022 02:59:10 GMT

By the way, where can I find PCA10112 DK user guide?

Thanks

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Thu, 06 Jan 2022 02:13:13 GMT

Hi Nordic team

Could you comment it?

I had no way to implement nrf21540 FEM at nRF Connect bluetooth examples.

Jeff

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Mon, 03 Jan 2022 07:20:24 GMT

Hi Jared

I doubted the FEM driver of DTM can be used in BLE examples.

At DTM, application code can control radio peripheral. So, it can set FEM driver in advance before radio TX or RX enabled.

However, at BLE examples, radio is dominated by BLE controller but not by appliction code. I have no idea when to set FEM driver.

Jeff

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jared — Tue, 21 Dec 2021 13:54:17 GMT

At this point we don't have that many BLE examples that use the FEM, but the DTM example supports it. You can try to "copy" the FEM driver that is included in that example,

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Tue, 21 Dec 2021 09:42:10 GMT

Besides,

For radio_test, it set FEM without BLE controller.

For bluetooth samples, how to set FEM with BLE controller?

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Tue, 21 Dec 2021 01:26:52 GMT

Hi Jared

As Nordic released sdk connect, why not to initially set the FEM configurations at kconf file of nrf21540dk_nrf52840 folder? It's more convenient for us to verify FEM.

Jeff

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Tue, 21 Dec 2021 01:20:19 GMT

Hi Jared

Appreciate your quick reply.

I cannot fine how to set 21540 FEM configurations at SDK Connect documentation website.

Would you kindly give an example for setting to me?

Jeff

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jared — Mon, 20 Dec 2021 12:04:09 GMT

Yes, but you also need to configure the FEM in your application by setting the wanted TX power etc.

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jeffery — Mon, 20 Dec 2021 07:55:16 GMT

Hi Jared

I know radio test can work nrf21540 FEM to enhance radio signal.

But, in my thought, Nordic already defined configurations of nrf21540 FEM.

If we enable these configurations at prj.conf or kconf at any nrf bluetooth samples and selected DK board PCA10112 (nrf21540dk_nrf52840),

after compiling and flashing to DK, FEM can work correctly and enhance radio signal. No need to modify project code.

Is it correct for what I thought?

Thanks.

Jeffery

RE: RSSI of PCA10112 was weaker than RSSI of PC10056

Jared — Thu, 16 Dec 2021 14:12:50 GMT

Hi,

[quote user=""]What is the reason? Shall I add configurations at prj.conf file to enable FEM?[/quote]

Yes. You need to configure the FEM, if not then you can't be sure what state it's in. To add FEM support in your application follow this:

The radio test does already support this board with FEM. You can try to compare the nRF52840 with the nRF21540 development kit running similar settings with this example.

regards

Jared