Beware that this post is related to an SDK in maintenance mode
More Info: Consider nRF Connect SDK for new designs
This post is older than 2 years and might not be relevant anymore
More Info: Consider searching for newer posts

Certification of custom board

Hi,

We are in a stage where we want to perform certification of a product and are now looking into an application that can be used to this end. The board is using SDK 15.0 and nrf52840.

We want to perform Radio, EMC and FCC tests.

The radio tests are going to be :

  • Tx: Constant carrier -->modulation Low, Mid, and High
  • Rx: no beacon

EMC are going to be same as above Rx with USB com and some other tests with the application code.

Now to my question, I have asked in a previous case if the dtm application could be used to this end, and got the answer that it should be possible . However, in other posts that I have seen, the support have mentioned that the radio example application would be suitable option when performing these test. In addition, I have started with the dtm application for a while and haven't quite understood how these additional settings could be configured. I have only managed to configure the device to respective state, i.e., Tx and Rx with the dtm application. Is it possible to configure these setting like no beacon, constant carrier with modulation low, mid, and high with the dtm application and how? If not should I instead be using the radio example code for this purpose?

Any help and guidance would be appreciated!

Sorry if I ask a lot of questions, since this is the first time I am going to be a part of the certification process and have no experience from before

Thanks in advance!

Best regards

Hadi

Parents
  • Hi Hadi,

     

    This

     

    Is it possible to configure these setting like no beacon, constant carrier with modulation low, mid, and high with the dtm application and how? If not should I instead be using the radio example code for this purpose?

     

    For this it would be easier to use the radio test example. The DTM application is designed to be used with a BLE tester and is only responding to DTM specific commands, documented in the Bluetooth Core spec. It is probably possible to send a raw command through a terminal, but you need to decipher the spec and construct the command. An alternative could be to use e.g. nRFgo Studio to send the commands, but the functionality might be limited (e.g. no 2 Mbps/LR) as nRFgo Studio is no longer maintained.

     

    Best regards,

    Andreas

  • Hi Andreas,

    Thank you for the clarification, I really appreciate it!

    We are currently using a python script that sends the initial setup commands like length, channel, data rate before performing the tests to the device using dtm application. I just have a few last questions regarding the modulation low, mid and high, constant carrier, and beacon off.

    Q1: When it comes to modulation low, mid and high, are these the channel settings, e.g., low would equal CH 0 and high would be the maximum channel, e.g., in nRFgo studio which is CH 39?

    Q2: The constant carrier is this the packet type, which in this case would be DTM_PKT_VENDORSPECIFIC?

    #define DTM_PKT_PRBS9                   0x00                                /**< Bit pattern PRBS9. */
    #define DTM_PKT_0X0F                    0x01                                /**< Bit pattern 11110000 (LSB is the leftmost bit). */
    #define DTM_PKT_0X55                    0x02                                /**< Bit pattern 10101010 (LSB is the leftmost bit). */
    #define DTM_PKT_0XFF                    0x03                                /**< Bit pattern 11111111 (Used only for coded PHY). */
    #define DTM_PKT_VENDORSPECIFIC          0x03                                /**< Vendor specific PKT field value. Nordic: Continuous carrier test, or configuration. */
    #define DTM_PKT_TYPE_VENDORSPECIFIC     0xFF                                /**< Vendor specific packet type for internal use. */

    Q3: Lastly, is it possible to turn off the beacon on the device. if so how could this be achieved? Is it available somewhere in the same ble_dtm.h header file so I could have a look at the cmd?

    Thanks in advance!

    /Hadi

  • Hi,

     

    1. Yes, nRFgo Studio maps channel n to frequency as 2402 MHz + 2*n MHz, meaning channel 39 is 2402 MHz + 2*39 MHz = 2480 MHz. Low is typically 2402 MHz, mid 2440 MHz and high 2480 MHz, except for 2 Mbps where channel 0 and 39 (2402 MHz and 2480 MHz, respectively) are not used. You should then use channel 1 and 38 (2404 MHz and 2478 MHz.) 

    2. It depends on the length parameter in the packet, see the example documentation. Constant carrier is one of the option though as you say.

    3. I am not sure I understand what you mean. Running the DTM example without any other application the board/device will not run any BLE activity. If you issue either of the DTM commands, the device will either transmit packets constantly per the channel and bit pattern you have instructed, or enter receive mode constantly. There will not be any BLE activity or transmissions other than what you have issued per DTM commands.

     

    Best regards,

    Andreas

Reply
  • Hi,

     

    1. Yes, nRFgo Studio maps channel n to frequency as 2402 MHz + 2*n MHz, meaning channel 39 is 2402 MHz + 2*39 MHz = 2480 MHz. Low is typically 2402 MHz, mid 2440 MHz and high 2480 MHz, except for 2 Mbps where channel 0 and 39 (2402 MHz and 2480 MHz, respectively) are not used. You should then use channel 1 and 38 (2404 MHz and 2478 MHz.) 

    2. It depends on the length parameter in the packet, see the example documentation. Constant carrier is one of the option though as you say.

    3. I am not sure I understand what you mean. Running the DTM example without any other application the board/device will not run any BLE activity. If you issue either of the DTM commands, the device will either transmit packets constantly per the channel and bit pattern you have instructed, or enter receive mode constantly. There will not be any BLE activity or transmissions other than what you have issued per DTM commands.

     

    Best regards,

    Andreas

Children
Related