TWI/I2C no communication with Sensor Devices

[Bjoern Bialy]

Hello,

my first Post here, so i hope i do it correctly.

I have the following Problem with the Configuration and Communication over TWI/I2C.

The Voltage of the TWI/I2C Bus is not 3.3V.

Reference Mesurment with a RPI and ESP32 for the same Sensor Hardware. I can say it's not a hardware fault.

---

I use as Hardwarebase the nRF52833-DK.

As Development runtime Zephyr with the nRF connect SDK V2.0.0 in Visual Studio Code.

As Test-Project to find the Problem, i use the follwing Code and Settings:

The used Overlay for I2C

&i2c0 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	pinctrl-0 = <&i2c0_default>;
	pinctrl-1 = <&i2c0_sleep>;
	pinctrl-names = "default", "sleep";
	clock-frequency = <100000>;
	/*adxl372@53 {
		compatible = "adi,adxl372";
		reg = <0x53>;
		int1-gpios = <&gpio0 54 GPIO_ACTIVE_HIGH>;
		label = "ADXL372";
	};*/
    /*pca9536@41 {
        compatible = "ti,pca9536";
        reg = <0x41>;
        label = "PCA9536";
    };
	gyro_adc@40 {
		compatible = "i2c-device";
		reg = < 0x40 >;
		label = "gyro";
	};
	bq35100@55 {
		compatible = "i2c-device";
		reg = < 0x55 >;
		label = "bms";
	};*/
};

and run it with this Project Configuration

CONFIG_STDOUT_CONSOLE=y
CONFIG_PRINTK=y

CONFIG_NEWLIB_LIBC=y
CONFIG_CPLUSPLUS=y
CONFIG_STD_CPP17=y
CONFIG_LIB_CPLUSPLUS=y
#CONFIG_RTTI=y
CONFIG_THREAD_ANALYZER=y
CONFIG_DEBUG=y
CONFIG_NEWLIB_LIBC_MIN_REQUIRED_HEAP_SIZE=2048

CONFIG_I2C=y
CONFIG_I2C_NRFX=y
CONFIG_I2C_GPIO=y
CONFIG_NRFX_TWI0=y

Source-Code (main.cpp):

/*
 * Copyright (c) 2015 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr.h>
#include <sys/printk.h>

#include <device.h>
#include <devicetree.h>
#include <drivers/gpio.h>
#include <drivers/i2c.h>

#define FRAM_I2C_ADDR 41

#define MY_TWIM DT_NODELABEL(i2c0)

void main(void)
{
	const struct device *i2c_dev = DEVICE_DT_GET(DT_NODELABEL(i2c0));
	uint8_t cmp_data[16];
	uint8_t data[16];
	uint8_t w_data[16];
	uint8_t r_data[16];
	int i, ret;
	int rc1, rc2, rc3, rc4;
	rc1 = rc2 = rc3 = rc4 = -999;

	//Initalisierung Speicehr Bereiche
	for (i = 0; i < 16; ++i)
	{ data[i] = w_data[i] =  r_data[i] = 0; }

	while (1)
	{
		if (!device_is_ready(i2c_dev))
		{ printk("I2C: Device is not ready.\n"); return; }	
		else
		{ printk("I2C: is ready.\n"); break; }
	}

	uint32_t dev_config = I2C_SPEED_SET(I2C_SPEED_STANDARD) | I2C_MODE_MASTER;

	if (i2c_configure(i2c_dev, dev_config))
	{ printk("Configure Fault\n"); }
	else
	{
		printk("Configure Done\n");
		/*printk("I2C Master: Slave ADDR: 0x%x SCL: %d, SDA: %d, CLK(Hz): %u\n\n",
          DT_REG_ADDR(DT_NODELABEL(i2c_dev)), 
          DT_PROP(MY_TWIM, pinctrl-0),
          DT_PROP(MY_TWIM, pinctrl-1),
          DT_PROP(MY_TWIM, clock_frequency));*/
	}

	k_sleep(K_MSEC(1));

	//Auslesen Config ist nicht Implementiert Fehler -88 ENOSYS
	//uint32_t dev_config_tmp;
	//rc1 = i2c_get_config(i2c_dev, &dev_config_tmp);
	//if (rc1 != 0) {
	//	printk("I2C get_config failed\n");
	//}
	//if (dev_config != dev_config_tmp) {
	//	printk("I2C get_config returned invalid config\n");
	//}

	uint8_t reg_to_read = 3;

	w_data[0] = reg_to_read;

	uint8_t wr_addr[2];
	/* FRAM address */
	wr_addr[0] = reg_to_read;
	wr_addr[1] = 0x00;
	struct i2c_msg msgs[2];
	/* Send the address to read from */
	msgs[0].buf = wr_addr;
	msgs[0].len = 2U;
	msgs[0].flags = I2C_MSG_WRITE;

	/* Read from device. STOP after this. */
	msgs[1].buf = data;
	msgs[1].len = 1;
	msgs[1].flags = I2C_MSG_READ | I2C_MSG_STOP;

	rc1 = i2c_write(i2c_dev, &wr_addr[0], 1, (uint16_t)FRAM_I2C_ADDR);
	rc2 = i2c_read(i2c_dev, &data[0], 1, (uint16_t)FRAM_I2C_ADDR);
	rc3 = i2c_write_read(i2c_dev, (uint16_t)FRAM_I2C_ADDR, &w_data[0], 1, &r_data[0], 1);
	rc4 = i2c_transfer(i2c_dev, &msgs[0], 2, (uint16_t)FRAM_I2C_ADDR);
	//read_byte(i2c_dev, 0x00, &data[0], FRAM_I2C_ADDR);
	if (rc1 == 0 || rc2 == 0 || rc3 == 0 || rc4 == 0)
	{ 
		printk("all read. \n");
		printk("Value write data: %d \n", w_data);
		printk("Value read data: %d \n", r_data);
	}
	else
	{ printk("read fault \n"); }
	
	return;
}

NRF-Terminal Output:

Connected via Serial Port with settings COM3 115200 8n1 rtscts:off

*** Booting Zephyr OS build v3.0.99-ncs1  ***
I2C: is ready.
Configure Done
read fault
*** Booting Zephyr OS build v3.0.99-ncs1  ***
I2C: is ready.
Configure Done
read fault
[00:00:09.736,724] <err> i2c_nrfx_twim: Error 0x0BAE0001 occurred for message 0
[00:00:09.736,938] <err> i2c_nrfx_twim: Error 0x0BAE0001 occurred for message 0
[00:00:09.737,121] <err> i2c_nrfx_twim: Error 0x0BAE0001 occurred for message 0
[00:00:09.737,304] <err> i2c_nrfx_twim: Error 0x0BAE0001 occurred for message 0

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The Project-Copy:

I2C-Test.zip

Thanks for Help