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]

Hello,

I can recommend a tutorial written by my colleague Simon. Chapter 1.2 should be of special interest for you:

https://devzone.nordicsemi.com/nordic/nrf-connect-sdk-guides/b/getting-started/posts/nrf-connect-sdk-tutorial---part-3-ncs-v1-4-0#h79sk0f70607qwcyitkx2xn61bmh9mo

Note that the tutorial is not up to date anymore, so instead of using

CONFIG_I2C_1=y

in prj.conf, you have to use this option instead:

CONFIG_I2C=y

I hope this will help you! Let me know if you have any more questions.

Regards,

Markus

[madblue]

Hi,

That is pretty good, thanks.

 

I have tried a simple test code for spi but i am not able to get the device_get_binding().

prj.config

CONFIG_NCS_SAMPLES_DEFAULTS=y

CONFIG_BT=y
CONFIG_BT_PERIPHERAL=y
CONFIG_BT_DEVICE_NAME="Nordic_Blinky"

# Enable the LBS service
CONFIG_BT_LBS=y
CONFIG_BT_LBS_POLL_BUTTON=y
CONFIG_DK_LIBRARY=y

CONFIG_GPIO=y
CONFIG_SPI=y
CONFIG_I2C=n
CONFIG_NRFX_SPIM=n
CONFIG_NRFX_SPIM1=n


CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048

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

    struct device * spi_dev;
    spi_dev = device_get_binding(DT_LABEL(SPI1));   


	const char* const spiName = "SPI_1";
	//spi_dev = device_get_binding(spiName);
    spi_dev = device_get_binding(MYSPI);
	if (spi_dev == NULL) {
		printk("Could not find SPI driver\n");
		return;
	}else printk("spi success");
	
	
	uint8_t tx_buf[4]={(0x0F<<1 ) | 0x01};
	uint8_t rx_buf[4]={0};
	struct spi_buf spi_tx_buf_struct;
	spi_tx_buf_struct.buf = tx_buf;
	spi_tx_buf_struct.len = 4;

	struct spi_buf spi_rx_buf_struct;
	spi_tx_buf_struct.buf = rx_buf;
	spi_tx_buf_struct.len = 4;

	struct spi_buf_set spi_bufs;
	spi_bufs.buffers = &spi_tx_buf_struct;
	spi_bufs.count = 4;
	struct spi_buf_set spi_bufs_rx;
	spi_bufs.buffers = &spi_rx_buf_struct;
	spi_bufs.count = 4;
	//


	spi_transceive(spi_dev, &spi_cfg, &spi_bufs, &spi_bufs_rx);
	//spi_write(spi_dev, &spi_cfg, &spi_bufs);
	k_sleep(K_MSEC(100));
	printk("read %d %d %d \n\n", rx_buf[1], rx_buf[2], rx_buf[3]);

I have also had a look at the "device tree how to  ",

my .dts for 52840,

&spi1 {
	compatible = "nordic,nrf-spi";
	/* Cannot be used together with i2c0. */
	/* status = "okay"; */
	sck-pin = <13>;
	mosi-pin = <14>;
	miso-pin = <16>;
};

zephyr.dts, 

spi1: spi@40004000 {
	#address-cells = < 0x1 >;
	#size-cells = < 0x0 >;
	reg = < 0x40004000 0x1000 >;
	interrupts = < 0x4 0x1 >;
	status = "disabled";
	label = "SPI_1";
	compatible = "nordic,nrf-spi";
	sck-pin = < 0xd >;
	mosi-pin = < 0xe >;
	miso-pin = < 0x10 >;
};

I think It initializes the spi, my i am getting this error,

*** Booting Zephyr OS build v2.4.99-ncs1  ***␍␊
Starting Bluetooth Peripheral LBS example␍␊
 SPI init␍␊
spi successI: CS control inhibited (no GPIO device)␍␊
E: ***** BUS FAULT *****␍␊
E:   Precise data bus error␍␊
E:   BFAR Address: 0x20040000␍␊
E: r0/a1:  0x40004000  r1/a2:  0x20002e1c  r2/a3:  0x0003dbb8␍␊
E: r3/a4:  0x20002448 r12/ip:  0x20002e28 r14/lr:  0x0001da9b␍␊
E:  xpsr:  0x21000014␍␊
E: Faulting instruction address (r15/pc): 0x00024216␍␊
E: >>> ZEPHYR FATAL ERROR 0: CPU exception on CPU 0␍␊
E: Fault during interrupt handling␍␊

I have tied the cs pin low always.

Do i have to specify the pin numbers elsewhere other than the .dts file ? does it get override from somewhere else ?