twi sensor i am not getting the data

[pavan_142297]

hi,

i am using nrf52832 devkit and max30208 temp. sensor. i am not getting updated data. iprefer this link for i2c address.(https://os.mbed.com/users/cyberjoey/code/OT07_I2C_GUI_Firmware//file/2e7483c7281b/main.cpp/) 

source code 

/** @file
* @defgroup tw_sensor_example main.c
* @{
* @ingroup nrf_twi_example
* @brief TWI Sensor Example main file.
*
* This file contains the source code for a sample application using TWI.
*
*/

#include <stdio.h>
#include "boards.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "nrf_drv_twi.h"
#include "nrf_delay.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

/* TWI instance ID. */
#define TWI_INSTANCE_ID 0

/* Common addresses definition for temperature sensor. */
#define max30208_slave_add 0x50U // (0x50U >> 1)
#define max30208_config 0x01U
#define max30208_read_data 0x08U
#define max30208_temp_setup 0x14U
#define max30208_temp_setup_value 0xC1U

#define LM75B_REG_TEMP 0x00U
#define LM75B_REG_CONF 0x01U
#define LM75B_REG_THYST 0x02U
#define LM75B_REG_TOS 0x03U

#define OT07_FIFO_DATA 0x08U // read temp. data
#define OT07_ADC_SETUP 0x14 // OT07 Temp Seneor Setup (ADC_RES[7:6]) & Convert Temperature [0]
/* Mode for LM75B. */
#define NORMAL_MODE 0U

/* Indicates if operation on TWI has ended. */
static volatile bool m_xfer_done = false;

/* TWI instance. */
static const nrf_drv_twi_t m_twi = NRF_DRV_TWI_INSTANCE(TWI_INSTANCE_ID);

double Temp_sample;

static void temp_tx_setup(void)
{
m_xfer_done = false;
ret_code_t err_code;
uint8_t reg[2] = {max30208_temp_setup, max30208_temp_setup_value};
err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, sizeof(reg), false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);

}

static void temp_rx_setup(void)
{
ret_code_t err_code;
m_xfer_done = false;
char data[2];
uint16_t count;
uint8_t reg[1] = {max30208_read_data};
err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, 2, false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);

err_code = nrf_drv_twi_rx(&m_twi, max30208_read_data, data, 2);
APP_ERROR_CHECK(err_code);
NRF_LOG_INFO("Temperature:data %d ", count);

/**
* @brief Function for setting active mode on MMA7660 accelerometer.
*/
void max30208_setmode(void)
{
ret_code_t err_code;

/* Writing to LM75B_REG_CONF "0" set temperature sensor in NORMAL mode. */
uint8_t reg[2] = {max30208_config, NORMAL_MODE};
err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, sizeof(reg), false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);

/* Writing to pointer byte. */
/* reg[0] = OT07_ADC_SETUP;
err_code = nrf_drv_twi_tx(&m_twi, LM75B_ADDR, reg, 1, false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);*/

/* reg[0] = OT07_FIFO_DATA;
m_xfer_done = false;
err_code = nrf_drv_twi_tx(&m_twi, LM75B_ADDR, reg, 1, false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);*/
}

/**
* @brief Function for handling data from temperature sensor.
*
* @param[in] temp Temperature in Celsius degrees read from sensor.
*/
__STATIC_INLINE void data_handler(double temp)
{
//NRF_LOG_INFO("Temperature: %lf, int %d Celsius degrees.",temp, (int) temp);
}

/**
* @brief TWI events handler.
*/
void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context)
{
switch (p_event->type)
{
case NRF_DRV_TWI_EVT_DONE:
if (p_event->xfer_desc.type == NRF_DRV_TWI_XFER_RX)
{
data_handler(Temp_sample);
NRF_LOG_INFO("data sent event");
}
m_xfer_done = true;
break;
default:
break;
}
}

/**
* @brief UART initialization.
*/
void twi_init (void)
{
ret_code_t err_code;

const nrf_drv_twi_config_t twi_lm75b_config = {
.scl = ARDUINO_SCL_PIN,
.sda = ARDUINO_SDA_PIN,
.frequency = NRF_DRV_TWI_FREQ_400K,
.interrupt_priority = APP_IRQ_PRIORITY_HIGH,
.clear_bus_init = false
};

err_code = nrf_drv_twi_init(&m_twi, &twi_lm75b_config, twi_handler, NULL);
APP_ERROR_CHECK(err_code);

nrf_drv_twi_enable(&m_twi);
}

/**
* @brief Function for reading data from temperature sensor.
*/
static void read_sensor_data()
{
temp_tx_setup();

nrf_delay_ms(500);
m_xfer_done = false;
char data[2];
uint16_t count;
ret_code_t err_code;
uint8_t reg[1] = {max30208_read_data};
err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, 2, false);
APP_ERROR_CHECK(err_code);
while (m_xfer_done == false);

err_code = nrf_drv_twi_rx(&m_twi, max30208_read_data, data, 2);
APP_ERROR_CHECK(err_code);
//calculate temperture from data
count = (uint16_t)(data[0]*256 + data[1]);
if (count >= 32768)
{count = 65536 - count;}
Temp_sample = (double)(count * 0.005);
NRF_LOG_INFO("Temperature data: %d , %X ", ,Temp_sample);
}

/**
* @brief Function for main application entry.
*/
int main(void)
{
APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
NRF_LOG_DEFAULT_BACKENDS_INIT();
NRF_LOG_INFO("\r\nTWI sensor example started.");

NRF_LOG_FLUSH();
twi_init();
max30208_setmode();

while (true)
{
nrf_delay_ms(500);

do
{
__WFE();
}while (m_xfer_done == false);

read_sensor_data();
NRF_LOG_FLUSH();
}
}

/** @} */

[Dmitry]

Hi,

it's really hard to read the code you posted, pleas use "insert code" menu. What strikes the eye:

- I2C address is expected as 7 bits without "W" bit (as I understand, 0x50 >> 1 in your case)
- did you connect sensor's GPIO pins to ground, to get proper I2C address?
- try lower speed (100k) first
- you have defined one-byte command (max30208_read_data) but writing two bytes
- you're not waiting for m_xfer_done after rx operation in read_sensor_data()

[pavan_142297]

Hi Dmitry,

as u suggested, I did changes in my code. and I also preferred  max30208 code from here

(https://os.mbed.com/users/cyberjoey/code/OT07_I2C_GUI_Firmware//file/2e7483c7281b/main.cpp/)

the code is working without convert temp. function. but data is not updating. we need to use that function to update temp.

please look into this.

#include <stdio.h>
#include "boards.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "nrf_drv_twi.h"
#include "nrf_delay.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

/* TWI instance ID. */
#define TWI_INSTANCE_ID     0

/* Common addresses definition for temperature sensor. */
#define max30208_slave_add         0x50U // (0x50U >> 1)
#define max30208_config            0x01U
#define max30208_read_data         0x08U
#define max30208_temp_setup        0x14U
#define max30208_temp_setup_value  0xC1U

#define LM75B_REG_TEMP      0x00U
#define LM75B_REG_CONF      0x01U
#define LM75B_REG_THYST     0x02U
#define LM75B_REG_TOS       0x03U

//#define OT07_FIFO_DATA      0x08U   // read temp. data
//#define OT07_ADC_SETUP      0x14    // OT07 Temp Seneor Setup (ADC_RES[7:6]) & Convert Temperature [0]
/* Mode for LM75B. */
#define NORMAL_MODE 0U

/* Indicates if operation on TWI has ended. */
static volatile bool m_xfer_done = false;

/* TWI instance. */
static const nrf_drv_twi_t m_twi = NRF_DRV_TWI_INSTANCE(TWI_INSTANCE_ID);

double Temp_sample;

#define OT07_STATUS         0x00    // OT07 status regiter
#define OT07_INT_EN         0x01    // OT07 Interrupt Enable
#define OT07_FIFO_W         0x04    // OT07 FIFO Write Pointer
#define OT07_FIFO_R         0x05    // OT07 FIFO Read Pointer
#define OT07_FIFO_OF        0x06    // OT07 FIFO Overflow Counter
#define OT07_FIFO_COUNT     0x07    // OT07 FIFO Data Count
#define OT07_FIFO_DATA      0x08    // OT07 FIFO Data
#define OT07_FIFO_CNFG1     0x09    // OT07 FIFO Configuration 1 (FIFO_A_FULL)
#define OT07_FIFO_CNFG2     0x0A    // OT07 FIFO Configuration 2
#define OT07_SYS            0x0C    // OT07 System Configuration
#define OT07_ALARM_HIGH_MSB 0x10    // OT07 Alarm High MSB
#define OT07_ALARM_HIGH_LSB 0x11    // OT07 Alarm High LSB
#define OT07_ALARM_LOW_MSB  0x12    // OT07 Alarm Low MSB
#define OT07_ALARM_LOW_LSB  0x13    // OT07 Alarm LOW LSB
#define OT07_ADC_SETUP      0x14    // OT07 Temp Seneor Setup (ADC_RES[7:6]) & Convert Temperature [0]
#define OT07_GPIO_SETUP     0x20    // OT07 GPIO Setup,  sets GPIO modes
#define OT07_GPIO_CTRL      0x21    // OT07 GPIO control
#define OT07_ROM_ID         0x31    // OT07 ROM_ID address of LSB?


void OT07_write_register(char I2C_add, char reg_add, char byte){
    char data[2];
    ret_code_t err_code;
    data[0] = reg_add;
    data[1] = byte;
    err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, data, 2, false);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false);
    NRF_LOG_INFO("wr[%02X %02X]\r\n", data[0], data[1]);
    
}

void OT07_read_register(char I2C_add, char reg_add, char *bytes, int n){
    ret_code_t err_code;
     err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, &reg_add, 1, 1);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false); 

    err_code = nrf_drv_twi_rx(&m_twi, max30208_slave_add, bytes, n);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false);
    
}


void convert_temperature(char I2C_add){   // set convert bit to start conversion

    char data[2];  
    
    //read ADC_SETUP register 0x14
    OT07_read_register(I2C_add, OT07_ADC_SETUP,data,1);       

    //mask convert register value with 0x01 and write back register 0x14      
    OT07_write_register(I2C_add, OT07_ADC_SETUP, data[0]|0x01);
}


/**
 * @brief Function for setting active mode on MMA7660 accelerometer.
 */
void max30208_setmode(void)
{
    ret_code_t err_code;

    /* Writing to LM75B_REG_CONF "0" set temperature sensor in NORMAL mode. */
    uint8_t reg[2] = {max30208_config, NORMAL_MODE};
    err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, sizeof(reg), false);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false);

}

/**
 * @brief Function for handling data from temperature sensor.
 *
 * @param[in] temp          Temperature in Celsius degrees read from sensor.
 */
__STATIC_INLINE void data_handler(double temp)
{
    NRF_LOG_INFO("Temperature: int %d Celsius degrees.",temp);
}

/**
 * @brief TWI events handler.
 */
void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context)
{
    switch (p_event->type)
    {
        case NRF_DRV_TWI_EVT_DONE:
            if (p_event->xfer_desc.type == NRF_DRV_TWI_XFER_RX)
            {
                data_handler(Temp_sample);
                NRF_LOG_INFO("data sent event");
            }
            m_xfer_done = true;
            break;
        default:
            break;
    }
}

/**
 * @brief UART initialization.
 */
void twi_init (void)
{
    ret_code_t err_code;

    const nrf_drv_twi_config_t twi_lm75b_config = {
       .scl                = ARDUINO_SCL_PIN,
       .sda                = ARDUINO_SDA_PIN,
       .frequency          = NRF_DRV_TWI_FREQ_400K,
       .interrupt_priority = APP_IRQ_PRIORITY_HIGH,
       .clear_bus_init     = false
    };

    err_code = nrf_drv_twi_init(&m_twi, &twi_lm75b_config, twi_handler, NULL);
    APP_ERROR_CHECK(err_code);

    nrf_drv_twi_enable(&m_twi);
}



/**
 * @brief Function for reading data from temperature sensor.
 */
static void read_sensor_data()
{
    m_xfer_done = false;
    char data[2];
    uint16_t count;
    ret_code_t err_code;
    uint8_t reg[1] = {max30208_read_data};
    err_code = nrf_drv_twi_tx(&m_twi, max30208_slave_add, reg, 1, false);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false);
   
    err_code = nrf_drv_twi_rx(&m_twi, max30208_slave_add, data, 2);
    APP_ERROR_CHECK(err_code);
    while (m_xfer_done == false);
    //calculate temperture from data     
    count = (uint16_t)(data[0]*256 + data[1]);
    if (count >= 32768)
    {count = 65536 - count;} 
    Temp_sample = (double)(count * 0.005); 
    NRF_LOG_INFO("Temperature data: debug  %d ", Temp_sample);
}  
    

/**
 * @brief Function for main application entry.
 */
int main(void)
{
    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
    NRF_LOG_DEFAULT_BACKENDS_INIT();
    NRF_LOG_INFO("\r\nTWI sensor example started.");

    NRF_LOG_FLUSH();
    twi_init();
     max30208_setmode();

    while (true)
    {
        nrf_delay_ms(500);

        do
        {
            __WFE();
        }while (m_xfer_done == false);
        convert_temperature(max30208_slave_add);
        nrf_delay_ms(20);
        read_sensor_data();
        NRF_LOG_FLUSH();
    }
}

[ondoindia]

hey Pavan,

Were you able to proceed with convert_temperature?

Regards

alok

[Quangca]

hello Ondoindia.

I also have the same issue don't get temperature data.

I try both to address 0x50 and (0x50>>1)

Can you let me know what exactly Max30208 address?

[ondoindia]

We have used 0x50U, it works!

#define max30208_slave_add         0x50U

[ondoindia]

It also depends on GPIO0 and GPIO1 being high or low, the other address could be 0x51U