Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Hakon — Thu, 24 Sep 2020 09:19:47 GMT

Please make a separate ticket for this.

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

ChandraSR K — Wed, 23 Sep 2020 13:22:06 GMT

I tried the code the works for you. but i am getting below error

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Yusuke — Thu, 27 Feb 2020 15:48:34 GMT

This works for me

Windows10
nrf v1.2.0

main.c

#include <zephyr.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <drivers/i2c.h>
#include <device.h>

#define I2C_ACCEL_ADDR (0x32 >> 1)
#define ACCEL_REG_WHO_AM_I 0x0F

struct device *i2c_2;

u8_t configure_accelerometer() {

    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x20, 0x2F) != 0) { // CTRL_REG1 (20h), Enable x,y,z axis, 10Hz, normal mode
            return -1;
    }
    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x21, 0x01) != 0) { // CTRL_REG2 (21h), High-pass filter enabled for AOI function on Interrupt 1.
            return -1;
    }
    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x22, 0x40) != 0) { // CTRL_REG3 (23h), IA1 interrupt on INT1 pin enable
            return -1;
    }
    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x30, 0x2A) != 0) { // INT1_CFG (30h), Enable interrupt generation on X,Y,Z high event or on direction recognition
            return -1;
    }
    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x32, 0x08) != 0) { // INT1_THS (32h), 1 LSb = 16 mg, threshold = 128mg
            return -1;
    }
    if (i2c_reg_write_byte(i2c_2, I2C_ACCEL_ADDR, 0x33, 0x00) != 0) { // INT1_DURATION (33h), Set the minimum duration of the Interrupt 1 event to be recognized
            return -1;
    }

    return 0;
}

void main(void)
{
    u8_t rx_buf[1];
    int8_t ret;

    i2c_2 = device_get_binding("I2C_2");
    if (!i2c_2) {
        sys_reboot(0);
    }

    if(configure_accelerometer() != 0) {
        sys_reboot(0);
    }

    u8_t reg = ACCEL_REG_WHO_AM_I;

    while (1) {
        printk("loop head\r\n");
        ret = i2c_burst_read(i2c_2, I2C_ACCEL_ADDR, reg, rx_buf, sizeof(rx_buf));
        if(ret == 0){ /* success */
            printk( "Read:  register = 0x%02X, value = 0x%02X\r\n", reg, rx_buf[0]);
        } else { /* ret = -EIO */
            printk( "i2c_burst_read fail!, register = 0x%02X, ret = %d\r\n", reg, ret);
        }

        k_sleep(3000);
    }            
}

prj.conf

# General
CONFIG_TRUSTED_EXECUTION_NONSECURE=y
CONFIG_AT_HOST_LIBRARY=n
CONFIG_SERIAL=y

# I2C
CONFIG_I2C=y
CONFIG_I2C_NRFX=y
CONFIG_I2C_2=y
CONFIG_I2C_2_NRF_TWIM=y

# Rebooot
CONFIG_REBOOT=y

# SEGGER RTT for Dev
CONFIG_PRINTK=y
CONFIG_CONSOLE=y
CONFIG_STDOUT_CONSOLE=y
CONFIG_UART_CONSOLE=n
CONFIG_RTT_CONSOLE=y
CONFIG_USE_SEGGER_RTT=y

nrf9160_pca10090ns.overlay

&i2c2 {
	status = "okay";
	sda-pin = <15>;
	scl-pin = <16>;
	clock-frequency = <100000>; 
};

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Jagruti — Thu, 27 Feb 2020 14:06:47 GMT

Hello Yusuke,

I'm also trying to communicate nRF9160 DK with an external accelerometer using I2C. I want to read the accelerometer and gyroscope values. I tried your code. When I don't connect the accelerometer, Error on i2c_read() is displayed which is correct. But when I connect the accelerometer nothing prints. The program stops there. After "loop head" nothing is printed on the terminal. Did you face the same problem? Do you know how to print the accelerometer values?

Thanks

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Yusuke — Fri, 29 Mar 2019 15:49:17 GMT

I created a new project and implemented almost same code. Then it works. I don't really figure out what was wrong. Anyway, this works.

#include <nrf9160.h>
#include <zephyr.h>
#include <misc/printk.h>
#include <i2c.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>

#define I2C_ACCEL_WRITE_ADDR 0x32
#define I2C_ACCEL_READ_ADDR 0x33

struct device *i2c_accel;
uint8_t WhoAmI = 0u;

uint8_t init_accelerometer(){
    i2c_accel = device_get_binding("I2C_1");
    if (!i2c_accel) {
		printk("error\r\n");
        return -1;
	} else  {
                i2c_configure(i2c_accel, I2C_SPEED_SET(I2C_SPEED_STANDARD));
        return 0;
    }
}

void main(void)
{
        printk("Hello, World!\r\n");
        init_accelerometer();

	while (1) {
                printk("loop head\r\n");

                if (i2c_reg_read_byte(i2c_accel, I2C_ACCEL_READ_ADDR >> 1, 0x0F, &WhoAmI) != 0) {
                        printk("Error on i2c_read()\n");
                } else {
                        printk("no error\r\n");
                }

                printk("WhoAmI = %u\r\n", WhoAmI);
                printk("enter sleep\r\n");
                k_sleep(3000);
	}
}

<prj.conf>
CONFIG_TRUSTED_EXECUTION_SECURE=y
CONFIG_SERIAL=y
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_I2C=y
CONFIG_I2C_NRFX=y
CONFIG_I2C_1=y
CONFIG_I2C_INIT_PRIORITY=60

<overlay file>
/* needed to get the NRF_UARTE2 defined */
&uart2 {
	current-speed = <1000000>;
	status = "ok";
	tx-pin = <18>;
	rx-pin = <17>;
	rts-pin = <19>;
	cts-pin = <21>;
};

&i2c1 {
	status = "ok";
	sda-pin = <10>;
	scl-pin = <11>;
	clock-frequency = <100000>; 
};

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

mtsunstrum — Fri, 29 Mar 2019 03:42:53 GMT

Nope I do not have nRF9160

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Yusuke — Fri, 29 Mar 2019 00:16:26 GMT

I will inspect the code this weekend. By the way, can you reproduce the symptom on your nRF9160? Even If no I2C device is connected, "Error on i2c_read()" should be displayed if I2C works correctly.

I'm using nRF91, not nRF52.

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

mtsunstrum — Wed, 27 Mar 2019 20:10:33 GMT

Also, before nrfx_twim_xfer() is executed, use your JTAG debugger to show all the values in nrfx_twim_xfer_desc_t data structure.

Paste that data structure contents in this forum, so we can all help you with this issue.

Info info info ...

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

mtsunstrum — Wed, 27 Mar 2019 20:08:25 GMT

Keep going ....

'res' tells you the result status. What is the value of 'res' ?

And when you look in the nRF52 documentation what does that value of 'res' indicate as a possible reason for the failure ?

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Yusuke — Wed, 27 Mar 2019 12:17:47 GMT

<i2c.h>

static inline int _impl_i2c_transfer(struct device *dev,
				     struct i2c_msg *msgs, u8_t num_msgs,
				     u16_t addr)
{
	const struct i2c_driver_api *api =
		(const struct i2c_driver_api *)dev->driver_api;

	return api->transfer(dev, msgs, num_msgs, addr);
}

After the debugger reaches "return api->transfer", I2C seems to be stacked.

When I step into "return api->transfer", debugging stops at a line of "if (res != NRFX_SUCCESS)"

<i2c_nrfx_twim.c>

static int i2c_nrfx_twim_transfer(struct device *dev, struct i2c_msg *msgs,
				  u8_t num_msgs, u16_t addr)
{
	for (size_t i = 0; i < num_msgs; i++) {
		if (I2C_MSG_ADDR_10_BITS & msgs[i].flags) {
			return -ENOTSUP;
		}

		nrfx_twim_xfer_desc_t cur_xfer = {
			.p_primary_buf  = msgs[i].buf,
			.primary_length = msgs[i].len,
			.address	= addr,
			.type		= (msgs[i].flags & I2C_MSG_READ) ?
					  NRFX_TWIM_XFER_RX : NRFX_TWIM_XFER_TX
		};

		nrfx_err_t res = nrfx_twim_xfer(&get_dev_config(dev)->twim,
					       &cur_xfer,
					       (msgs[i].flags & I2C_MSG_STOP) ?
					       0 : NRFX_TWIM_FLAG_TX_NO_STOP);
		if (res != NRFX_SUCCESS) { // STOP HERE
			if (res == NRFX_ERROR_BUSY) {
				return -EBUSY;
			} else {
				return -EIO;
			}
		}

		k_sem_take(&(get_dev_data(dev)->sync), K_FOREVER);
		res = get_dev_data(dev)->res;
		if (res != NRFX_SUCCESS) {
			LOG_ERR("Error %d occurred for message %d", res, i);
			return -EIO;
		}
	}

	return 0;
}

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

mtsunstrum — Tue, 26 Mar 2019 18:49:16 GMT

You are just showing us code only.

That does not help us help you.

With your JTAG debugger, you should be able to show the exact line of code that is giving you some problem.

Maybe to restate your question: nRF9160 stop working at the function of i2c_reg_read_byte in the code below.

For others to help you, you have to say exactly what is not working. "stop working" is not sufficient to help you.

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

Yusuke — Sat, 23 Mar 2019 13:02:28 GMT

Hi, mtsunstrum!. Thank you for your comment.

I took i2c_reg_read_byte from zephyr driver.

docs.zephyrproject.org/.../io_interfaces.html

the definition is below.

/**
 * @brief Read internal register of an I2C device.
 *
 * This routine reads the value of an 8-bit internal register of an I2C
 * device synchronously.
 *
 * @param dev Pointer to the device structure for the driver instance.
 * @param dev_addr Address of the I2C device for reading.
 * @param reg_addr Address of the internal register being read.
 * @param value Memory pool that stores the retrieved register value.
 *
 * @retval 0 If successful.
 * @retval -EIO General input / output error.
 */
static inline int i2c_reg_read_byte(struct device *dev, u16_t dev_addr,
				    u8_t reg_addr, u8_t *value)
{
	return i2c_burst_read(dev, dev_addr, reg_addr, value, 1);
}

RE: Trouble: TWI(I2C) stops at the function of i2c_reg_read_byte On nRF9160 DK. Why?

mtsunstrum — Fri, 22 Mar 2019 20:51:14 GMT

Do you have the source code for i2c_reg_read_byte() ?

If yes, you should be able to see the line(s) of code where it is stuck inside of i2c_reg_read_byte()

That would help us to help you further.

Thanks, Martin