Getting started with spi and i2c on nrf connect sdk

[madblue]

Hi,

I have been working with nrf5 sdk for my projects and now i am trying to port it into the nrfconnect sdk.

It looks a bit confusing and not able to find the proper documentation channels to add spi communication to my sample project. I have seen some of the posts here that looks out dated.

I couldn't make any progress in communicating with my device over spi or twi. 

What is simplest way to add an spi sensor ?

[Albrecht Markus Schellenberger]

Chapter 3.4 of Simons tutorial gives you a basic introduction on how to create an overlay file. I hope this will be useful for you.

Cheers!

Markus

[madblue]

Thanks Markus, 

it was helpful, i am able read/write data using the zephyr apis.

I am still a bit confused about the spi data structures for read/write and also the 'patch_spi_read' api.

It doesn't seem to work but i can figure that out. 

I will try out the i2c in the same way.

I have a general question regarding the nrfconnect sdk and zephyr,

As I have mentioned in the initial question, i am trying to port my application code to nrf connect sdk from nrf5 sdk14.00. i am a bit worried about the time required to completely port the code.

My application requirements are, 

dfu bootloader, 2 spi, a flash file system(little fs), extended BLE mtu size(>150), low BLE connection interval (<50 ms), 2 timers, 1 i2c and a watchdog.

Is the nrfconnect sdk drivers required for my application is mature enough? Is there enough examples/documentation available to make the process as quick as possible ?

Just to make sure it is the right time to port the code to nrfconnect sdk.

I am adding my code here. 

Hope this would be helpful for someone.

/*
 * Copyright (c) 2012-2014 Wind River Systems, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr.h>
#include <sys/printk.h>
#include <zephyr/types.h>
#include <stddef.h>
#include <string.h>
#include <errno.h>
#include <drivers/spi.h>
#include <drivers/gpio.h>


#if !DT_NODE_EXISTS(DT_NODELABEL(spi1))
#error "0oops"
#endif
#define SPI1 DT_NODELABEL(spi1)

int spi_cs_pin = 15;
int led_pin = 14;

static struct spi_config spi_cfg = {
	.operation = SPI_WORD_SET(8) | SPI_TRANSFER_MSB,
	.frequency = 4000000,
	.slave = 0,
};
struct device * spi_dev = NULL;
struct device * gpio0_dev = NULL;
struct device * gpio1_dev = NULL;

bool patch_spi_read(uint8_t * tx_ptr, uint8_t * rx_ptr, uint8_t tx_len, uint8_t rx_len){

	int err;

	struct spi_buf tx_buf[2];
	struct spi_buf rx_buf[2];
	struct spi_buf_set tx;
	struct spi_buf_set rx;

	tx_buf[0].buf = tx_ptr;
	tx_buf[0].len = 1;

	rx_buf[0].buf = rx_ptr;
	rx_buf[0].len = 1;

	rx_buf[1].buf = &rx_ptr[1];
	rx_buf[1].len = 4;

	tx.buffers = tx_buf;
	tx.count = 1;
	rx.buffers = rx_buf;
	rx.count = 2;

	gpio_pin_set(gpio0_dev, spi_cs_pin, 0);
	//err = spi_transceive(spi_dev, &spi_cfg, &tx, &rx);k_sleep(K_MSEC(30));
	err = spi_write(spi_dev, &spi_cfg, &tx);

	if (err) {
		printk("spi write error: %d\n", err);
		return false;
	}
	k_sleep(K_MSEC(3));
	err = spi_read(spi_dev, &spi_cfg, &rx);
	if (err) {
		printk("spi read error: %d\n", err);
		return false;
	}else {
		printk("tx data %x\n", tx_ptr[0]);

		for (size_t i = 0; i < 4; i++) {
			printk("RX recv: %d \n", rx_ptr[i]);
		}
	}
	//gpio_pin_set(gpio0_dev, spi_cs_pin, 1);
	return true;
}

void main(void)
{
	printk("Hello World! %s\n", CONFIG_BOARD);

	gpio0_dev= device_get_binding("GPIO_0");

	gpio_pin_configure(gpio0_dev, spi_cs_pin, GPIO_OUTPUT); //p0.03 == led_pin2
	gpio_pin_configure(gpio0_dev, led_pin, GPIO_OUTPUT); //p0.03 == LED2
	gpio_pin_set(gpio0_dev, spi_cs_pin, 0);


	printk(" SPI init\n");
	spi_dev = device_get_binding(DT_LABEL(SPI1));
	if (spi_dev == NULL) {
		printk("Could not find SPI driver\n");
		return;
	}else printk("spi init success\n");

	k_sleep(K_MSEC(50));

	static uint8_t tx_buffer[16] = {0x1f, 00, 00, 00};
	static uint8_t rx_buffer[16];
	patch_spi_read(tx_buffer, rx_buffer, 1, 4);

	while(true){
		gpio_pin_set(gpio0_dev, led_pin, 0xff);
		k_sleep(K_MSEC(2000));

		gpio_pin_set(gpio0_dev, led_pin, 0);
		k_sleep(K_MSEC(30));
	}

}