Latest DTM test for nRF52840

[Hiihtaja]

Hello !

You have DTM test in nRF5_SDK_17.1.0  and in nRF Connect SDK.

I have used SDK test some years ago and it looks more simple if we compare it with new environment,

 

What is real difference between those tests and do I really need new one ?

Also I should customize DTM test for custom FEM and in older it look simple to do it.

Could you explain differences in tests or/and what arguments exist for start usage of new test ?

Regards,

Eugene

[Kenneth]

Hello,

If I look at the latest DTM that was released in nRF5 SDK I can find that that it was targeted for DTM tests described in BT v5.2:
https://docs.nordicsemi.com/bundle/sdk_nrf5_v17.1.0/page/ble_sdk_app_dtm_serial.html 

So if there have been mandatory tests included in BT 5.3 and later for new BT features, then you may be missing those.

Also it looks like the nRF5340 is not mentioned in the nRF5 SDK, so you can't DTM from nRF5 SDK for that variant.

Also I believe that the FEM support in nRF5 SDK did not include support for the nRF21540 FEM, it may only have included support for a FEM from skyworks, but I may be wrong about this one. I mention it in any case.

But if your main reason for using DTM is to check the hardware and ensure it operates within specification, then there is nothing preventing you from using DTM from nRF5 SDK no.

Kenneth

[Hiihtaja]

Hello !

Thank you !

I have taken dtm test from SDK 17.1  for PCA10112 board . It have FEM. And Direct Test application v2.4,1 from nRFConnect for Desktop. 

But I can see max TX power what I can set via UI is +8dBm only. Looks like FEM is not visible to application and board identified as generic PCA10056.

Should It work someting like this or FEM setting should appears in UI as well ?

What about TX duty cycle setting ? Looks like it can be changed at all like in radio test application.

I have asked to cook TX with duty cycle 90% and no way to change it easily.

Regards,

Eugene

[Kenneth]

Hi Eugene,

Seen from the tester it will have no knowledge of the hardware really, it will just send commands to configure it in various DTM test modes as described by the BT DTM spec.

The only reason why you see PCA10056 mentioned is because the nRF connect for desktop recognize the board is a nRF52840-DK. Though you could in principle connect the UART pins on the PCA10056 to some other nRF device, and it would still say it's PCA10056.

The only difference when using a FEM is the ability to set higher output power, and actually get higher output power. 

I do not believe DTM support control of any kind of duty cycle, so you will need to use radio test for that purpose (with BLE modulation). The purpose of DTM is really only to verify that you fulfill the BT SIG requirements of radio characteristics. 

Kenneth