nRF52840 SDK16 - Problem with TWI

[Nikosant03]

Hi everyone, 

I try to write using I2C but I fail and I cannot figure out the issue

This is my code snippet.

uint8_t my_data[2];
  my_data[0] = 0x00;
  my_data[0] = 0x01;
  rslt = reg_write(reg_addr, my_data, 2, dev);
  
 --------------------------------------------------------------------------------------------
 
  uint8_t reg_write(uint8_t reg_addr, uint8_t *data, uint16_t len, struct BQ27421_dev *dev) {
  
  /*Call the I2C write function*/
  dev->write(dev->chip_id, reg_addr, data, len);
                  
}

//write() is a function pointer to Acc_i2c_Write()
 --------------------------------------------------------------------------------------------

int8_t Acc_i2c_Write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len) {

 
  int8_t rslt = 0;
  uint8_t data[len + 1];
  data[0] = reg_addr; 
  for (uint16_t i = 0; i < len; i++) {
    data[i + 1] = reg_data[i]; 
  }

  rslt = nrf_drv_twi_tx(&m_twi, dev_id, data, len + 1, false); 
  APP_ERROR_CHECK(rslt);



  return rslt;
}

When I run it it returns the following error

00> <error> app: ERROR 2 [NRF_ERROR_SOFTDEVICE_NOT_ENABLED] at C:\Users\n.antoniou\Dropbox\IoT\Nordic\nRF52840\nRF5_SDK_16.0.0\Ingenious\BLE_Peripheral\BLE_IMU_v4\main.c:484
00> PC at: 0x00034529
00> <error> app: End of error report

It fails inside the nrf_drv_twi_tx() function.. When I set the len parameter to one then it runs normally but I want to write two bytes..

Any ideas?

[Jared]

Hi,

Could you post more of your code? I'm not sure if it actually is asserting at that function since the error message is reporting that you haven't enabled the Softdevice and this is not a error that is returned by that function. Could you share your main file?

regards

Jared 

[Nikosant03]

Hi Jared,

I enable the Softdevice before initializing the TWI driver and finally my BMX160 and BQ27421 I2C sensors. This is my main()

int main(void) {

  log_init(); // na - Initialize the logger module

  createInterrupt();                             // Create the interrupts
  timers_init();                                 // na - Initialize the Timer Library
  power_management_init();                       // Initializing power management
  ble_stack_init();                              // BLE Stack initiallization
  sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE); // na - Enabling the DCDC converter for lower current consumption after calling ble_stack_init - You can enable the DC/DC at any time after you have enabled the SoftDevice
  gap_params_init();                             // GAP initiallization, the Generic Access Profile, specifies the ways devices advertise, discover and connect to each other
  gatt_init();                                   // GATT initiallization, the Generic Attribute Profile, is the one that handles attributes, characteristics and services
  services_init();                               // Initialize the services
  advertising_init();                            // Initilize the advertising

  conn_params_init();  // Initialize the connection parameters
  peer_manager_init(); // Initialize the Peer Manager Module. The peer manager module handles encryption, pairing, and bonding

  
  twi_init();
  Acc_delay_ms(50);

  BMI160_init();
  Acc_delay_ms(100);


  BQ27421_initialize(); // na - Initialize the battery monitor

  //***************SAADC-FLEXI FORCE***************
  nrf_gpio_range_cfg_output(pinStartOut, pinStopOut); // na - pinout for EB v.1
  selectMuxPin(callback_counter);                     // na - set the control pin of MUX to zero
  saadc_init();                                       // na -  consumes high current when the saadc is initiated. Check this example to minimize the consumption https://github.com/NordicPlayground/nRF52-ADC-examples/blob/master/saadc_low_power/main.c

  //---------------------------------------------------------------------------------------------------------------------------

  nrf_gpio_cfg_output(vibrator); // na - configure vibrator as OUTPUT
  nrf_gpio_pin_clear(vibrator);  // na - initialize the pin to low (no vibration)
  nrf_gpio_cfg_output(CTRL);     // na - configure the CTRL pin as output (this pin set and unset converter's LOAD output)
  nrf_gpio_pin_set(CTRL);        // Enable the LOAD output of buck converter (TPS62740) by setting high its CTRL pin
  nrf_delay_ms(10);              // na - add a small delay to give some time to complete the pin configuration

  /** @brief : RAM retention - Writes the NRF_POWER->RAM[index].POWERSET register
   *
   *  @param[in] index : Contains the index in the NRF_POWER->RAM[index].POWERSET register to write to.
   *  @param[in] ram_powerset : Contains the word to write to the NRF_POWER->RAM[index].POWERSET register.
   *
   *  @retval : NRF_SUCCESS
   */
  ret_code_t err_code;
  err_code = sd_power_ram_power_set(RAM_AHB_slave, POWER_RAM_POWER_S0RETENTION_On << POWER_RAM_POWER_S0RETENTION_Pos); // na - retain RAM AHB 2, index 0.
  APP_ERROR_CHECK(err_code);


  // Enter main loop.
  for (;;) {

    // Enter system On sleep mode
    idle_state_handle(); // na - The Power Management library is safer to use than the inline functions __SEV, __WFE, __WFI especially when SoftDevice is used.
  }
}

Thanks

[Jared]

Hi. 

Please share the whole file. The error is reporting that it asserts at line 484 in main.c