How can I use ERR_TO_STR_TWI() macro?

[ndarkness]

Hello,

I would like to understand how can I make use of the macro ERR_TO_STR_TWI in order to know what error is being given by my TWI module function.

I have tried something like this

  err_code = nrf_drv_twi_rx(&twi, reg_addr, rxData, bytesNumberRx);
  ERR_TO_STR_TWI(err_code);
  APP_ERROR_CHECK(err_code);

But it doesn't work at all, actually setting a breakpoint on ERR_TO_STR_TWI() shows how this call isn't invoked at all...

Any hints?

Thanks in advance

[Jørn]

Hello ndarkness

The ERR_TO_STR_TWI is defined in sdk_errors.h. For it to be defined NRF_LOG_ENABLED must be defined and set to 1. The macro is defined as

#define ERR_TO_STR_TWI(err_code)        m_sdk_errors_name_twi[err_code - NRF_ERROR_PERIPH_DRIVERS_ERR_BASE]

Where

#define NRF_ERROR_PERIPH_DRIVERS_ERR_BASE   (0x8200)

and

const char * m_sdk_errors_name_twi[ERR_NAMES_TWI_SIZE] =
{
    "NRF_ERROR_DRV_TWI_ERR_OVERRUN",
    "NRF_ERROR_DRV_TWI_ERR_ANACK",
    "NRF_ERROR_DRV_TWI_ERR_DNACK"
};

So calling ERR_TO_STR_TWI(err_code) alone wouldn't really do much as it just returns the pointer to a string, but doesn't do anything with it.

You could take the return value and output that using NRF_LOG_INFO(). A quick test

NRF_LOG_INFO("%s",(uint32_t)ERR_TO_STR_TWI(0x8202));

Outputted the expected result.

Best regards

Jørn Frøysa

[Jørn]

Hi Kyle,

The specific macros for converting error codes to strings doesn't seem to be described in the documentation. The macros are not present in the sdk_error.h file in any other version before, or after 12.2 and 12.3. My guess is it was an idea to implement them, which was later abandoned.