SPI configuration?

[venkatesha kj]

when i try to configure spi1 i am getting error, so how can i configure different spi ? 

[Einar Thorsrud]

Hi,

Can you explain which SDK you are using, how you configure your SPI and which error you get? Please elaborate.

[venkatesha kj]

/*
* DAC.c
*
* Created on: Nov 2, 2021
* Author: 91889
*/
#include "DAC.h"
#include "stdio.h"
//#include "main.h"
#include "nrf_drv_spi.h"
#include "nrf_gpio.h"
#include <string.h>

#define SPI_INSTANCE 0                                               /**< SPI instance index. */
static const nrf_drv_spi_t spi = NRF_DRV_SPI_INSTANCE(SPI_INSTANCE); /**< SPI instance. */
static volatile bool spi_xfer_done;

#define SPI_SS_PIN 31
#define SPI_MISO_PIN 30
#define SPI_MOSI_PIN 29
#define SPI_SCK_PIN 26
#define CS_Pin 5

#define VREF 2500
#define MULTIPLIER (65536 / VREF)

//extern SPI_HandleTypeDef hspi1;

void spi_event_handler(nrf_drv_spi_evt_t const *p_event,
                       void *p_context)
{
    spi_xfer_done = true;
    // NRF_LOG_INFO("Transfer completed.");
    /* if (m_rx_buf[0] != 0)
{
NRF_LOG_INFO(" Received:");
NRF_LOG_HEXDUMP_INFO(m_rx_buf, strlen((const char *)m_rx_buf));
}*/
}

void Spi0_init(void)
{
    nrf_drv_spi_config_t spi_config;
    spi_config.ss_pin = SPI_SS_PIN;
    spi_config.miso_pin = SPI_MISO_PIN;
    spi_config.mosi_pin = SPI_MOSI_PIN;
    spi_config.sck_pin = SPI_SCK_PIN;
    spi_config.frequency = NRF_SPI_FREQ_4M;
    spi_config.mode = NRF_SPI_MODE_0;
    spi_config.bit_order = NRF_SPI_BIT_ORDER_MSB_FIRST;
    APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, spi_event_handler, NULL));
}

void Dac_Input(uint8_t chanel, uint16_t value)
{
    static uint8_t m_tx_buf[] = {0};
    static uint8_t m_rx_buf[] = {0};
    static const uint8_t m_length = sizeof(m_tx_buf);
    float multipiler = (float)65536 / VREF;
    uint8_t tx_Buffer;
    uint16_t dac_Value;
    if (value == 2500)
    {
        dac_Value = 65535;
    }
    else
    {
        dac_Value = (uint16_t)(value * multipiler);
    }
    nrf_gpio_cfg_output(CS_Pin);
    nrf_gpio_pin_clear(CS_Pin);
    //HAL_GPIO_WritePin(GPIOA, CS_Pin, GPIO_PIN_RESET);
    if (chanel == channel_A)
    {
        memset(m_rx_buf, 0, m_length);
        spi_xfer_done = false;
        m_tx_buf[0] = 0x30;
        //HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
        nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, NULL);
        //HAL_Delay(50);
        //power_down channel_B
        // tx_Buffer = 0x41;
        // HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
    }
    else
    {
        memset(m_rx_buf, 0, m_length);
        spi_xfer_done = false;
        m_tx_buf[0] = 0x31;
        //HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
        nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, NULL);
        //HAL_Delay(50);
        //power_down channel_A
        // tx_Buffer = 0x40;
        // HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
    }
    memset(m_rx_buf, 0, m_length);
    spi_xfer_done = false;
    m_tx_buf[0] = (uint8_t)((dac_Value & 0xFF00) >> 8);
    //HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
    nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, NULL);
    memset(m_rx_buf, 0, m_length);
    spi_xfer_done = false;
    m_tx_buf[0] = (uint8_t)(dac_Value & 0x00FF);
    //HAL_SPI_Transmit(&hspi1, &tx_Buffer, 1, 100);
    nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, NULL);

    //HAL_GPIO_WritePin(GPIOA, CS_Pin, GPIO_PIN_SET);
    nrf_gpio_pin_set(CS_Pin);
}

[Einar Thorsrud]

Hi,

I took the liberty to format your C code for improved readability.

You write that the clock was not generated. That means that no SPI transaction was started, so I expect an error has occured. I notice in your code that you ignore most return values. That is a very bad idea, and the first thing you should do is to improve your code so that you check all return values using APP_ERROR_CHECK (particularly the return values from nrf_drv_spi_transfer()). Are there any errors here? What else do you see from debugging?

[venkatesha kj]

code was hanged here

while (!nrf_spim_event_check(p_spim, NRF_SPIM_EVENT_END))

[venkatesha kj]

How to transfer a data in blocking mode?

[Einar Thorsrud]

To use blocking mode you do not provide a event handler when you initialize the driver using nrf_drv_spi_init(). So in your code, you would change the call to nrf_drv_spi_init() like this:

    APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, NULL, NULL));

Then call nrf_drv_spi_transfer() like before (but fix it so that you check return values!) and the function will not return until the transaction has completed.

[venkatesha kj]

i am getting error like this

undefined reference to `nrfx_prs_acquire'

[Einar Thorsrud]

Ah, yes. I did not think about that. Assuming you have added the requiered include folder etc you are lacking the PRS configuraiton in sdk_config.h. Depending on which sdk_config.h you used as a starting point there may be more like this. Please search for NRFX_PRS_ENABLED and NRFX_PRS_BOX_4_ENABLED in sdk_config.h. You may need to do this with other components as well.