DTM +8dBm issue

[Atlas]

Hi

We want to set +8dBm on DTM with nRF52840 but it test fail.

When I set +8dBm, nRFgo Studio cannot test it due to fail in DTM code.

We tried SDK v14~ v15 version but it is always fail.

We also tried others command but some bugs in DTM code.

Please refer attach file and try in Nordic side.

Thanks.

AtlasDTM issue for nRF52840.pdf

[King501802]

I have the same issue.

Could it be fixed in next version of SDK?

[Rune Holmgren]

Hi,

The SDK team are aware of the issue, but unfortunately, the change didn't get added to SDK 15.0.0. It will be coming in the next SDK. For now, the following workaround can be added to get +8dBm support.

uint32_t dtm_radio_validate(int32_t m_tx_power, uint8_t m_radio_mode)
{
    // Initializing code below is quite generic - for BLE, the values are fixed, and expressions
    // are constant. Non-constant values are essentially set in radio_prepare().
    if (!(m_tx_power == RADIO_TXPOWER_TXPOWER_0dBm        ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Pos4dBm     ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg30dBm    ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg20dBm    ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg16dBm    ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg12dBm    ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg8dBm     ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg4dBm     ||
          m_tx_power == RADIO_TXPOWER_TXPOWER_Pos3dBm     ||
#ifdef NRF52840_XXAA
          m_tx_power == RADIO_TXPOWER_TXPOWER_Pos8dBm     ||
#endif //NRF52840_XXAA
          m_tx_power == RADIO_TXPOWER_TXPOWER_Neg40dBm
          ) ||

         !(

Best regards,
Rune Holmgren

[Atlas]

Hi

Thank you for update.

But we want to know when Nordic will fix this issue in official release SDK.

Beside nrf52840 +8dBm issue, there are some issues in my attach PDF file.

Please help to check the content.

Thanks.

BR

Atlas

[Rune Holmgren]

Hi,

Thank you for the detailed explanations and descriptions in the PDF. I will address each of them separately.

---

Q1)

This is a good point and as already discussed this will be resolved in the SDK. Thanks for pointing this out.

Q2)

As I understand it, the problem you are seeing here is that vendor specific commands are not available in LE coded PHY? I disagree that this is a problem. The table below is from the Bluetooth Core Specification version 5.0, volume 6, part F (page 2779):

In coded PHY the packet format 11111111 is available instead of vendor specific commands.

Let me know if I misunderstand you, or if you think I am reading the specification wrong.

Q3)

 Because of the reason explained above, it is not valid to set a TX power when you are in coded PHY. The packet to set TX power to -40 is actually a packet requesting the device to transmit 0xFF packets on frequency 2450MHz. The next command tries to set the device in TX mode, but it's already in TX mode so the command fails.

Q4)

 Are you wondering how to run either vendor specific or 0xFF packets? 0xFF packets are only available in coded PHYs. Vendor specific commands are only available when in non-coded PHYs.

---

I have tried to address the four issues you have pointed out, but feel free to point out anything I may be misunderstanding. If there are any unknown bugs in DTM we want to fix them. All feedback is very welcome.

Best regards,
Rune Holmgren