Delay between SPI clock and Data bytes in Zephyr nRF52832 - spi_transceive_dt()

RE: Delay between SPI clock and Data bytes in Zephyr nRF52832 - spi_transceive_dt()

Håkon Alseth — Thu, 30 Jan 2025 11:36:56 GMT

Hi,

Your spi1 instance uses the non-DMA capable "nordic,nrf-spi", so you will see a delay between transactions.

Please see my former answer on how to use "nordic,nrf-spim" (and its errata), which is the DMA capable peripheral.

Kind regards,

Håkon

RE: Delay between SPI clock and Data bytes in Zephyr nRF52832 - spi_transceive_dt()

pradeep8892 — Thu, 30 Jan 2025 10:41:06 GMT

Hi Håkon,

Please find the zephyr.dts file attached.

devzone.nordicsemi.com/.../0511.zephyr.dts

Warm regards,

Pradeep

RE: Delay between SPI clock and Data bytes in Zephyr nRF52832 - spi_transceive_dt()

Håkon Alseth — Thu, 30 Jan 2025 10:32:18 GMT

Hi,

Can you share your build/app-name/zephyr/zephyr.dts file?

By default, spi1 is using the non-DMA capable NRF_SPI peripheral:

https://github.com/zephyrproject-rtos/zephyr/blob/main/boards/nordic/nrf52dk/nrf52dk_nrf52832.dts#L200

If you change it to "nrf-spim" instead:

&spi1 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	pinctrl-0 = <&spi1_default>;
	pinctrl-1 = <&spi1_sleep>;
	pinctrl-names = "default", "sleep";
};

It will use DMA.

Please note that nRF52832 has a critical errata with SPIM: https://docs.nordicsemi.com/bundle/errata_nRF52832_Rev1/page/ERR/nRF52832/Rev1/latest/anomaly_832_58.html

If your device is not affected by this errata, you can set "CONFIG_SOC_NRF52832_ALLOW_SPIM_DESPITE_PAN_58=y" to override it.

Kind regards,

Håkon