SPI LoRa nRF52840

[Divya M]

Hi,

I am trying to do basic tx and rx by interfacing sx1262 and nRF52840 IC in our custom board we have used 100K pull-ups in miso and mosi lines for low power consumption. We observe that whenever we manually send status commands as per the sx1262 datasheet the return value is always 0x22 instead of 0x2A. Could you suggest the preliminary settings that should be done to correct our SPI configurations. 

Is there any additional configurations required to be made when using SPI in custom boards, can the SDK SPI example be used for custom boards ?

Note:

We have also tried to disable and enable the miso pull-up configuration in the SDKconfig.h file.

The SPI lines run at 2.5V.

We have changed the SPI pins (high speed) according to our custom design.

For debugging purpose I am not able to visualise the data in the Logic analyser it shows settings mismatch.

Thankyou.

[Divya M]

Hi,

I am waiting for your reply.

[Naeem Maroof]

Hello,

Thank you for your patience.

I do not find any reference to 0x22 or 0x2A in sx1262 datasheet.

To use the SPI settings,
we configure the node on spi-controller in the overlay. This should be done in consultation with the datasheet. For example, one of the customer pointed out issues with spi-communication and it turned out that the they were configuring reset-gpio wrong in the overlay.

In the application, you use the spi_config structure to use the configuration for your device. For example, what is the frequency, and what is the spi operation (done through flags, like MSB_first etc.

I recommend you to look at "lora send sample" in ncs 2.4.2.

BR, Naeem