Bluetooth direct test mode doesnt work for custom board

[NanElv]

Hi, I'm using a custom board with nrf52840, NCS version 2.3.0, zephyr 0.16.0

I'm trying to use the samples/bluetooth/direct_test_mode with the modified rx,tx pin information according to our cutomon board. 

I'm unable to estanblish the communication to the nrf desktop application for the direct test mode. 

I have seen several questions on this, and none of their solution works for me. 

The Desktop can see both the jlink and the USB/UART connections, but i cannot run any test. 

If i use jlink this is the error i'm getting this below given error.

if i use the usb/UART, i get this error

I'm not sure where the issue is, the sample i have tested both by copying into my own custom code, and on its own. I neither see any RTT message on the DTM, nor any serial communication. Any help would be much appreciated. 

Do i have to set anything specific for antenna as in nrf53xxx, in nrf52?

[runsiv]

Hi

In general we recommend testing with the radio test sample, are you able to run it on your custom board? https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/peripheral/radio_test/README.html It gives you a shell where you can adjust your radio parameters. 

I would expect the jlink instance to work so that makes sense to me. As for the DTM I need to investigate 

Regards

Runar

[NanElv]

I couldnt run the radio test too, this is my usb.overlay set based on the custom board. Do i have to set any connection between jlink and the UART on Realterm/Serial connection/putty? for it to work.  As of the hw connection is 

Custom board made with nrf52840 + USB/UART + the nrf DeskTop application. Do i also need additional nrf52840 DK with this?



This is the output i see for the radio test, atleast the DTM was making connection with the FTD, but this one not doing that too. 

[runsiv]

For the radio test sample you will need to use an terminal like for example putty to interface with the device. I don't expect the jlink to have any serial connection to the device, so I would not spend any time to look at that. Are you able to connect to the shell over usb? 

NanElv said:

Custom board made with nrf52840 + USB/UART + the nrf DeskTop application. Do i also need additional nrf52840 DK with this?

You can either test it with another DK or with the RSSI application in nRF Connect for Desktop. 

Regards

Runar

[NanElv]

I could make the nrf52840 + USB/UART + the nrf Desktop Serial connect to read the messages on the UART.  There is just one UART which is also used as J-link. But I could see the output of the RTT on the serial UART.  Is there any process for the Radio test, with the Radio test software, the device is not even recongnised.

also according to this, for bluetooth testing, its not recommended to use the radio test. 

 DTM or Radio Test 

[runsiv]

It dependes what you want to test really. it can be summarzied like this 

The Radio Test Example demonstrates how to configure the radio as the constant RX or TX carrier, the modulated TX carrier, or the RX or TX sweep.

While the DTM example is more advanced and its purpose is to test the operation of the radio at the physical level, such as:

• Transmission power and receiver sensitivity
• Frequency offset and drift
• Modulation characteristics
• Packet error rate
• Intermodulation performance

 See Radio Test Example and Direct Test Mode example documentation

So yes, the radio_test example is used for FCC and CE certification. The DTM example is primarly used for Bluetooth qualification , but can also be used for FCC/CE certification. 

ref this thread

I'm sorry but I keep mixes up a few cases. In this case you have a custom board with only one UART right and this goes through a Jlink? The uart pins looks fine from what I can see, and they are connect how to your computer?

Also did you include this in your overlay? I could not see it from the image

/ {
	chosen {
		ncs,dtm-uart = &uart0;
	};
};

The repones might be slow here since from end of word today until including Monday the 1. of April is public holidays here in Norway

Regards

Runar

[NanElv]

With the NCS upgraded to 2.6.0, I'm able to  do the direct test mode on the nrf desktop application, with the custom board. 

[runsiv]

Thats great to hear, best luck on further development

Regards

Runar