reading data from a sensor that has no driver using TWI

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Tue, 26 Apr 2022 09:09:19 GMT

Sorry for the slow response, I have been out of office for the last couple of weeks.

Are you still having issues with this? If anything has changed, maybe you could give me a status update?

I downloaded the datasheet, but there doesn't seem to be a description of the instruction set. Can this be found somewhere else?
If you have a link to a description of the instruction set, can you send me that also?

Best regards
Torbjørn

RE: reading data from a sensor that has no driver using TWI

Saed — Fri, 08 Apr 2022 12:18:34 GMT

they all return 0, here is the Datasheet and unfortunately, I don't have an analyzer at the moment

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Fri, 08 Apr 2022 11:06:17 GMT

Could you check the return code of the various i2c function calls to see if they run successfully?
If they return something other than 0 it meant something went wrong in the call to the function.

In particular the calls to i2c_write(), i2c_read() or i2c_write_read().

Are you able to check with a scope or logic analyzer what is happening on the I2C bus?

Do you have a datasheet you can share for the sensor, so I can have a look at it?

Best regards
Torbjørn

RE: reading data from a sensor that has no driver using TWI

Saed — Wed, 06 Apr 2022 10:42:45 GMT

Here is another example of the problem

void main(void)
{
	


	uint16_t twi_test_cnt = MSG_EXCHANGE_CNT;
	bool led_is_on = true;
	uint32_t ret;

	led_dev = device_get_binding(LED0);
	if (led_dev == NULL)
	{
		return;
	}

	ret = gpio_pin_configure(led_dev, PIN, GPIO_OUTPUT_ACTIVE | FLAGS);
	if (ret < 0)
	{
		return;
	}
	k_msleep(2000);
	int	incr = 0 ;
	int rtn_code = 5;

	twim_init();
	printk("\n"); 
	printk("\n-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-\n"); 
	printk("\n"); 
    k_msleep(2000);
	i2c_write(nrfx_twis_dev1,softRest,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) )	;
	k_msleep(2000);
	i2c_write(nrfx_twis_dev1,activateASC,4,DT_REG_ADDR(DT_NODELABEL(twis_device1)) );
	k_msleep(2000);
	i2c_write(nrfx_twis_dev1,getASC,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) );
	k_msleep(2000);
	i2c_read(nrfx_twis_dev1, i2c_rx_buffer, sizeof(i2c_rx_buffer), DT_REG_ADDR( DT_NODELABEL(twis_device1) ) );
	while (incr <4)
			printk("| 0x%.2x |", i2c_rx_buffer[incr++]);
	printk("\n"); 
	printk("\n-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-\n"); 
	printk("\n"); 

	incr = 0 ;
	k_msleep(2000);
	i2c_write_read(nrfx_twis_dev1, DT_REG_ADDR(DT_NODELABEL(twis_device1)),getASC,2,i2c_rx_buffer,18);
	while (incr< 4)
			printk("| 0x%.2x |", i2c_rx_buffer[incr++]);
	printk("\n"); 
	printk("\n-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-\n"); 
	printk("\n"); 
}

in this code I try to activate ASC: AUTO SELF CALIBRATION, I send the command to activate it then I send the command to get the ASC Status (both ways) and it returns 0 meaning it is not active

I have no clue how is this happening?!

RE: reading data from a sensor that has no driver using TWI

Saed — Wed, 06 Apr 2022 10:08:33 GMT

Hi, in the code I posted you can see that I have I2c_write_read() commented, that is because I tried using it as well, did not work with any command, however, I was able to get the frameware version ---> page 17 using separate I2C_write() then read, according to the scd30 Zephyr example:

https://github.com/Sensirion/embedded-common/blob/1ac7c72c895d230c6f1375865f3b7161ce6b665a/hw_i2c/sample-implementations/zephyr_user_space/sensirion_hw_i2c_implementation.c

when trying to write (Get measurement interval for example (page9) ) I always get the deafult interval for the sensor which is 2 sec, although I just used command (set Interval) to change it 4 sec!

when trying to get ( dataReady) it always returns 0 although I have already sent (triggerContinuous Measurement

I don't understand where is the problem

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Wed, 06 Apr 2022 07:49:54 GMT

Assuming your sensor expects a typical write -> repeated start -> read pattern where you first write the command and then immediately read out the response, then you should use the i2c_write_read(..) function.

Issuing separate i2c_write(..) and i2c_read(..) calls will most likely not have the same effect, since they will be interpreted by the sensor as two separate commands.

Best regards
Torbjørn

RE: reading data from a sensor that has no driver using TWI

Saed — Tue, 05 Apr 2022 08:34:16 GMT

hi,

I have attached a new code where I write commands to the sensor to start the measurement and get results, unfortunately, all that I get is 0xff 0xff 0xac

/*
 * Copyright (c) 2016 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

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



/* 1000 msec = 1 sec */
#define SLEEP_TIME_MS 10000

/* The devicetree node identifier for the "led0" alias. */
#define LED0_NODE DT_ALIAS(led0)

const struct device *led_dev;

#if DT_NODE_HAS_STATUS(LED0_NODE, okay)
#define LED0 DT_GPIO_LABEL(LED0_NODE, gpios)
#define PIN DT_GPIO_PIN(LED0_NODE, gpios)
#define FLAGS DT_GPIO_FLAGS(LED0_NODE, gpios)
#else
/* A build error here means your board isn't set up to blink an LED. */
#error "Unsupported board: led0 devicetree alias is not defined"
#define LED0 ""
#define PIN 0
#define FLAGS 0
#endif

////////////////////////////////////////////////////////////

// TWI Test Configuration

////////////////////////////////////////////////////////////

#define ECHO_WRITES true
#define MSG_EXCHANGE_CNT 5
#define INFINITE_MSG_EXCHANGE false
#define TWI_LOOPBACK false
// In non-loopback mode, the tx message is unchanged.
// In loopback mode the rx buffer acts as both the tx and rx buffer. The rx buffer is updated with each read.

////////////////////////////////////////////////////////////

// Adding TWI Functionality

////////////////////////////////////////////////////////////

#define TWI_BUFFER_SIZE 18
 
static const uint8_t readCommand[] = {0x03,0x00} ;
static const uint8_t dataReady[] = {0x02,0x02} ;
static const uint8_t triggerContinuousMeasurement[2] = {0x00,0x10} ;
static const uint8_t deactivateASC[] = {0x53, 0x06, 0x00, 0x00 } ;
static const uint8_t activateASC[2] = {0x53, 0x06 } ;
static const uint8_t getASC[] = {0x53, 0x06 } ;
static const uint8_t softRest[] = {0xD3,0x04} ;															
static const uint8_t framewareVersion[] = {0xD1,0x00} ;		 		

//5sec

static uint8_t i2c_rx_buffer [TWI_BUFFER_SIZE];

// TWI Master Setup

#define MY_TWIM DT_NODELABEL(i2c2)
const struct device *nrfx_twis_dev1;


static void twim_init(void)
{
	int config_result = false;
 

	nrfx_twis_dev1 = device_get_binding(DT_LABEL(MY_TWIM));
	printk("\n\nI2C Slave: Device driver not found.\n");
	if (nrfx_twis_dev1 == NULL)
	{
		printk("\n\nI2C Slave: Device driver not found.\n");
	}
	else
	{
		printk("\nI2C device 1: %s\n", DT_PROP(DT_NODELABEL(twis_device1), label));

		config_result = i2c_configure(nrfx_twis_dev1, I2C_SPEED_SET(I2C_SPEED_FAST) | I2C_MODE_MASTER);

		if (!config_result)
		{
			printk("I2C Master: Slave ADDR: 0x%x SCL: %d, SDA: %d, CLK(Hz): %u\n\n",
				   DT_REG_ADDR(DT_NODELABEL(twis_device1)),
				   DT_PROP(MY_TWIM, scl_pin),
				   DT_PROP(MY_TWIM, sda_pin),
				   DT_PROP(MY_TWIM, clock_frequency));
		}
		else
			printk("\n\nI2C: Configuration error code: %d\n", config_result);
			
	}
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// TWI Master Write
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
void twi_write_tst()
{
	int rtn_code = 0;
	uint8_t incr = 0;
     

	if (nrfx_twis_dev1 != NULL)
	{
		 printk("\nTWIM TX/writing.");
	 
		  // write repeated default message
			rtn_code = i2c_write(nrfx_twis_dev1, activateASC ,2, DT_REG_ADDR(DT_NODELABEL(twis_device1)));
		 	printk("\nTWIM TX/writing ----->        rtn_code: %d",rtn_code);
	 
		if (ECHO_WRITES && (rtn_code == 0))
		{/* 
			printk("\nTWIM TX:");
			while (incr < 2)
				printk("| 0x%.2x |", buffur[incr++]);
			printk("\n"); */
		} // rtn_code == 0

		if (rtn_code)
		{
			printk("twi return code %u\n\n", rtn_code);
		}
	}
	else // twis_dev1 == NULL
		printk("TWIS device is not initialized correctly.\n");
} 

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Checking if data is ready or not 
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////

uint8_t getReadyStatus(void)
{	

	// printk("\n GETTING READY STATUS!! ");
	int rtn_code = 0;
	uint8_t incr = 0;


	if (nrfx_twis_dev1 != NULL)
	{
		// printk("\nTWIM TX/writing.");
	 
		  // write repeated default message
			rtn_code = i2c_write(nrfx_twis_dev1, dataReady , 2 , DT_REG_ADDR(DT_NODELABEL(twis_device1)));
		 	 // printk("\nTWIM TX/writing  /dataReady/ -----> rtn_code: %d",rtn_code);
	 
		/* if (ECHO_WRITES && (rtn_code == 0))
		{
			printk("\nTWIM TX:");
			while (incr < 2)
				printk("|  %d  |", dataReady[incr++]);
			printk("\n");
		} // rtn_code == 0
 */
		/* if (rtn_code)
		{
			printk("twi return code %u\n\n", rtn_code);
		} */
	}
	else // twis_dev1 == NULL
	//	printk("TWIS device is not initialized correctly.\n");

    rtn_code = 0;
	incr = 0;
	k_msleep(5);	
	if (nrfx_twis_dev1 != NULL)
	{
		
	//	printk("\nTWIM RX/reading -->");
		rtn_code = i2c_read(nrfx_twis_dev1, i2c_rx_buffer, sizeof(i2c_rx_buffer), DT_REG_ADDR( DT_NODELABEL(twis_device1) ) );
		

		/* print the result */

		if (rtn_code == 0)
		{
	/* 		printk("TWIM RX:");
			while (incr < TWI_BUFFER_SIZE)
			{
				printk(" | %d  | ", i2c_rx_buffer[incr++]);
			};
			printk("\n");
			 */
			 
		}

		if (rtn_code)  printk("twi return code %u\n\n", rtn_code);
	}
	else // twim_dev1 == NULL
		printk("TWI is not initialized correctly.\n");

return i2c_rx_buffer[1] ;

} 

void twi_read_tst(void)
{
	int rtn_code = 0;
	uint8_t incr = 0;

	if (nrfx_twis_dev1 != NULL)
	{
		
		printk("\nTWIM RX/reading -->");
		rtn_code = i2c_read(nrfx_twis_dev1, i2c_rx_buffer, sizeof(i2c_rx_buffer), DT_REG_ADDR( DT_NODELABEL(twis_device1) ) );
		

		/* print the result */

		if (rtn_code == 0)
		{
			printk("TWIM RX:");
			while (incr < TWI_BUFFER_SIZE)
			{
				printk(" | 0x%.2x  | ", i2c_rx_buffer[incr++]);
			};
			printk("\n");
		}

		if (rtn_code)  printk("twi return code %u\n\n", rtn_code);
	}
	else // twim_dev1 == NULL
		printk("TWI is not initialized correctly.\n");
}

void main(void)
{
	uint16_t twi_test_cnt = MSG_EXCHANGE_CNT;
	bool led_is_on = true;
	uint32_t ret;

	led_dev = device_get_binding(LED0);
	if (led_dev == NULL)
	{
		return;
	}

	ret = gpio_pin_configure(led_dev, PIN, GPIO_OUTPUT_ACTIVE | FLAGS);
	if (ret < 0)
	{
		return;
	}

	twim_init();
	k_msleep(2000);
	i2c_write(nrfx_twis_dev1,softRest,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) )	;
	k_msleep(2000);

	int rtn_code = 5;
	int	incr = 0 ;
	i2c_write(nrfx_twis_dev1,triggerContinuousMeasurement,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) )	;
	k_msleep(2000);
	i2c_write(nrfx_twis_dev1,activateASC,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) );
	k_msleep(2000);
	i2c_write(nrfx_twis_dev1,dataReady,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) );
	k_msleep(2000);
	i2c_read(nrfx_twis_dev1, i2c_rx_buffer, sizeof(i2c_rx_buffer), DT_REG_ADDR( DT_NODELABEL(twis_device1) ) );
 	while (1)
	{

		gpio_pin_set(led_dev, PIN, (int)led_is_on);
		led_is_on = !led_is_on;

		if ((twi_test_cnt) || (INFINITE_MSG_EXCHANGE))
		{		
			incr = 0 ;
			// i2c_write_read(nrfx_twis_dev1, DT_REG_ADDR(DT_NODELABEL(twis_device1)),readCommand,2,i2c_rx_buffer,18);
			i2c_write(nrfx_twis_dev1,readCommand,2,DT_REG_ADDR(DT_NODELABEL(twis_device1)) );
			i2c_read(nrfx_twis_dev1, i2c_rx_buffer, sizeof(i2c_rx_buffer), DT_REG_ADDR( DT_NODELABEL(twis_device1) ) );
 			while (incr < 18)
			printk("| 0x%.2x |", i2c_rx_buffer[incr++]);
			printk("\n"); 
			
			
		}
		k_msleep(10000);
	}
}

devzone.nordicsemi.com/.../blinky_2D00_TWIM3.zip

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Mon, 04 Apr 2022 10:31:01 GMT

Hi Saed

Can you show me the code you used to produce this printout?

I don't see "0x" printed anywhere, so I must assume you didn't copy my code exactly.

Best regards
Torbjørn

RE: reading data from a sensor that has no driver using TWI

Saed — Fri, 01 Apr 2022 14:35:16 GMT

thanks for your continuous support, I tried the hex and the decimal representation it looks like this!

kind regards

Saed

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Fri, 01 Apr 2022 09:26:13 GMT

Good to hear you got the sensor working 🙂

Most likely the data from the sensor will not make sense in ASCII presentation.

You could try to print the data as hex or int values instead. To print as hex with at minimum two digits presentation, you can do it like this:

int hex_val = 0x12;
printk("Hex value: 0x%.2x", hex_val);

Best regards
Torbjørn

RE: reading data from a sensor that has no driver using TWI

Saed — Thu, 31 Mar 2022 15:54:54 GMT

Hi, thank you for your reply I was able to find the device using the scanner and I was also able to fix the previous code and it flashed successfully, the only problem now is that the readings from the sensor are printed in weird characters devzone.nordicsemi.com/.../blinky_2D00_TWIM_2D00_updated.zip

RE: reading data from a sensor that has no driver using TWI

ovrebekk — Thu, 31 Mar 2022 10:37:37 GMT

If you just want to get I2C running you can do this quite easily, without making any changes to the device tree configuration.

I added a small example showing how to do this, based on the blinky sample in Zephyr:

devzone.nordicsemi.com/.../3513.i2c_5F00_scanner.zip

If you run this example with your I2C sensor connected it should print out the I2C address of your sensor, assuming everything is connected properly.

Best regards
Torbjørn