Development Issues When Using the nRFx Library in Zephyr

[joey]

HI，

I am currently developing with nRF54L15 and SDK 3.0.0. I have encountered some issues:
1. Problems using the nrfx library in Zephyr
I have defined the configuration information of the SPIM30 node in the devicetree. According to the Zephyr manual, this configuration is initialized before running the application. Therefore, I directly obtained the instance of spim30 in the program and used the nrfx spim library to send data. However, I found that the originally set 8M in devicetree was actually only 1M, and the CS pin output level was supposed to be high after transmission but remained low. But when I directly used the Zephyr spi API, there was no problem. The nrfx is shown in the following figure. Why is this happening?How to deal with this problem?

2. I have used nrfx in Zephyr and set CONFIG_DEVICE_PM_RUNTIME. Does it have no effect?
3. In my program, I am using grtc + dppi + spim, all of which are using nrfx library functions. How should the power management of spim be handled? Since I am using the nrfx library and only using dppi to trigger?

Thanks!

[Vidar Berg]

Hello,

The configurations from your spi30 node in the devictree will not be automatically applied when you are using the nrfx drivers directly like they are when using the Zephyr SPI driver API. Please verify that .frequency value passed to nrfx_spim_init() is configured correctly.

https://github.com/zephyrproject-rtos/zephyr/blob/e9cf74b581a1371f77862eea1e3cf24cadd457c6/samples/boards/nrf/nrfx_prs/src/main.c#L145 

Best regards,

Vidar

[joey]

Thank you for your reply

After initializing SPIM with nrfx_spim_init, I was able to communicate normally by calling nrfx_spim_xfer. Then, I configured the DMA array list and used nrfy_spim_task_trigger(spim30_inst.p_reg, NRF_SPIM_TASK_START) to trigger the task. However, when observing the oscilloscope, there were no waveforms and the program was not running properly. What could be the problem?

[Vidar Berg]

You should avoid direct register access when using the driver like you are doing in sensor_spim_dma_init(). Otherwise the driver is likely to end up overwriting your configurations.

You can set up your transfers via nrfx_twim_xfer(). See API documentation for relevant flags and helper macros.

[joey]

However, in the SDK I'm using, I couldn't find the configuration function for the DMA array list, and some of the examples I've looked at also directly accessed the registers.

Now I want to use DPPI to control SPIM. So even though NRFX_TWIM_XFER can be used for transmission, it does not meet the actual application requirements for me.

[Vidar Berg]

Array list mode is enabled with the NRFX_TWIM_FLAG_TX_POSTINC and NRFX_TWIM_FLAG_RX_POSTINC flags. There is also the NRFX_TWIM_FLAG_HOLD_XFER to configure a transaction without actually starting it.

[joey]

However, these functions of mine are undefined.,How should it be set to be enable?