How to configure Lora as TCXO in Sidewalk

[666]

Hi all,

    In Sidewalk, the Lora we are using is connected to DIO3 through TCXO, which does not match the XTAL of sx1262 recommended by the official sid_end_device demo. Do you have any suggestions?

[Menon]

Hello,

We haven't tested it, so all we can suggest is that if your configuration works well, using it might not be an issue. If you wish, you can send us the configuration code(in zip or via Git) for the Nordic DK with the SX126 shield, and we will review it.

You might find a similar implementation on the RAK board. Therefore, we recommend testing it yourself to see if this design causes any issues. Please let us know the results.

Kind Regards,
Abhijith

[666]

Hi,

I also want to ask, in the Lora driver of Sidewalk, is ANT_SW pulled up and the lora driver controls the RF transmission and reception through DIO2?

[Menon]

Hello,

If you look into the LoRA driver, you will see that SX126xIoRfSwitchInit() does indeed configure DIO2 to control the RF switch, specifically setting it up for TX enable mode. Take a look at this old DevZone case and also refer to the section on setting up the hardware.

Kind regards,
Abhijith

[666]

Hi ,

Menon said:

If you look into the LoRA driver, you will see that SX126xIoRfSwitchInit() does indeed configure DIO2 to control the RF switch, specifically setting it up for TX enable mode

Are you saying that the Lora driver for Sidewalk also uses the same Lora driver from Zephyr? In this case, when I run Sidewalk, can I configure CONFIG_LORA_LOG_LEVEL=4 to debug the running status of Lora in Sidewalk？

[Menon]

Hello,

666 said:

Are you saying that the Lora driver for Sidewalk also uses the same Lora driver from Zephyr?

Sidewalk is not using the LoRa driver from Zephyr. Sorry for the confusion caused by pointing to the Zephyr driver. However, the Sidewalk driver behaves similarly to the Zephyr driver when it comes to DI02. See the details here.

The RF switch is controlled via a GPIO pin. See this part of the driver implementation, and this part sets the GPIO direction. The antenna switch diagram you shared looks correct.

666 said:

In this case, when I run Sidewalk, can I configure CONFIG_LORA_LOG_LEVEL=4 to debug the running status of Lora in Sidewalk？

It's not possible to use Zephyr LoRa driver logs with Sidewalk. However, it is possible to get more control over Semtech by using SIDEWALK_PAL_RADIO_SOURCE. You can enable this configuration, but you will need to add the Semtech sources from the Semtech addon.

Kind Regards,

Abhijith