SPI Timout waiting for transfer complete

[Stefan Nienhuis]

Hi there,

I'm having an issue with the SPI master in Zephyr. When attempting to transmit data it returns the error: 'Timeout waiting for transfer to complete'. Am I missing something here?

main.c:

#include <zephyr/kernel.h>
#include <zephyr/logging/log.h>
#include <zephyr/drivers/spi.h>

#define PN76_SPI DT_NODELABEL(pn76_spi)
#define PN76_SPI_OP (SPI_OP_MODE_MASTER | SPI_TRANSFER_MSB | SPI_WORD_SET(8) | SPI_LINES_SINGLE)

LOG_MODULE_REGISTER(app);

void main(void) {
  struct spi_dt_spec pn76_spi = SPI_DT_SPEC_GET(PN76_SPI, PN76_SPI_OP, 0);

    bool ready = spi_is_ready(&pn76_spi);
    LOG_INF("Ready: %i", ready);

    unsigned char buffer[20] = { 0 };
    unsigned int length = sizeof(buffer);

    const struct spi_buf tx_buffer = {
        .buf = buffer,
        .len = length
    };

    const struct spi_buf_set tx_buffers = {
        .buffers = &tx_buffer,
        .count = 1
    };

    int status = spi_write_dt(&pn76_spi, &tx_buffers);
    LOG_INF("Status: %i", status);

	k_sleep(K_FOREVER);
}

DTS overlay:

/ {
    zephyr,user {
        pn76-enable-gpios = <&gpio1 10 GPIO_ACTIVE_LOW>;
        pn76-dwl-req-gpios = <&gpio1 11 GPIO_ACTIVE_HIGH>;
        pn76-irq-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH>;
    };
};

&pinctrl {
    spi1_default: spi1_default {
        group1 {
            psels = <NRF_PSEL(SPIM_SCK, 0, 8)>,
                    <NRF_PSEL(SPIM_MOSI, 0, 6)>,
                    <NRF_PSEL(SPIM_MISO, 0, 7)>;
        };
    };

    spi1_sleep: spi1_sleep {
        group1 {
            psels = <NRF_PSEL(SPIM_SCK, 0, 8)>,
                    <NRF_PSEL(SPIM_MOSI, 0, 6)>,
                    <NRF_PSEL(SPIM_MISO, 0, 7)>;
            low-power-enable;
        };
    };
};

&spi1 {
	compatible = "nordic,nrf-spim";
    status = "okay";

	pinctrl-0 = <&spi1_default>;
	pinctrl-1 = <&spi1_sleep>;
    cs-gpios = <&gpio0 5 GPIO_ACTIVE_LOW>;

    pn76_spi: spi-dev-a@0 {
        compatible = "vnd,spi-device";
        reg = <0>;
        spi-max-frequency = <1600000>;
    };
};

prj.conf:

CONFIG_SPI=y
CONFIG_LOG=y

Logs:

*** Booting Zephyr OS build v3.2.99-ncs1 ***
[00:00:00.373,657] <inf> app: Ready: 1
[00:00:00.573,791] <err> spi_nrfx_spim: Timeout waiting for transfer complete
[00:00:00.573,822] <inf> app: Transmit status: -116

nRF Connect version: v2.2.0

Zephyr version: 3.2.99

Best regards,

Stefan Nienhuis

[Turbo J]

The SPIM0-2 only allow up to 8 MHz on SCK. Only the bug-ridden SPIM3 allows for up to 32 MHz on the NRF52840 - but look into the errata sheet first.

[Stefan Nienhuis]

Thanks for the response. It was set to 1.6 Mhz, so that wasn't the issue. 

The issue was apparently the selected GPIOs on the devkit. It seems these are used for something else, which resulted in this error message.

[HashSplash]

Hi Stefan, I'm getting the same error but only during an interrupt operation. Can you please tell me what worked for you exactly and why you were facing this issue in the first place?

[PoloMetyos]

I had the same issue and removed the reading during the interrupt, using a semaphore instead of performing the spi operation in the main loop.

Here is another topic talking about this issue.
NCS/Zephyr SPIM: issue triggering spi_transceive from counter ISR

The strange thing to me is that it was working well most of the time but sometimes crashed (BUS FAULT) when I used 2.5.1, and it was always triggering a timeout when upgrading to 2.6.1.
Anyway, it seems to work now that I don't perform a reading during the interrupt.