BLE DTM Test (nRF52840) — Direct Test Mode V1.1.7 Plugin Fails to Open After Installation

[Frank Cai]

Bluetooth physical layer Direct Test Mode testing is used to verify BLE low-level RF transceiver performance. The required software is nRF Connect for Desktop V3.7 + Direct Test Mode V1.1.7 plugin. The PC is unable to properly install the DTM V1.1.7 plugin, and the latest version of Direct Test Mode cannot be used for testing either.

[Kenneth]

Hello,

Why do you seemingly use very old nRF Connect for Desktop and DTM app?

I think the latest is v5.3.1 and v3.1.2 for those two apps.

Kenneth

[Frank Cai]

Hello Kenneth,

Because the previous development was done using nRF Connect for Desktop V3.7 + Direct Test Mode V1.1.7 plugin.

However, recently we found that it no longer works. Also, when using the latest version of the app, Direct Test Mode cannot obtain any data.

Is it because the latest version of the app does not support the nRF52840?

Frank

[Kenneth]

Hello,

You may need to manually build the direct test mode example from source and program it first, follow:
https://docs.nordicsemi.com/bundle/ncs-3.3.0/page/nrf/samples/bluetooth/direct_test_mode/README.html 

Depending if you are testing on your own hardware, it may be that you should consider setting the following in the direct test mode example.

If you don't have any antenna matrix, then use in overlay:

&radio {
    /delete-property/ dfe-supported;
};

If you don't have any external 32kHz crystal, then use in config:

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_XTAL=n

If you don't have any DCDC circuitry, then using in overlay:

&reg1 {
	regulator-initial-mode = <NRF5X_REG_MODE_LDO>;
};

In the direct test mode app, notice there are two comports, so if the first doesn't work, then try the second.

Hope that helps,
Kenneth