nrf52 TWI error code

[kenearl]

Hi,

I am trying to write a I2C read and write wrappers for Invensense MPU9250. Previously, I was using SDK11 and I don't have any issue with it. However, after porting the code into the new SDK nRF5_SDK_12.2.0_f012efa, i kept getting errors. However, the error did not surface immediately, it's after a short period of continuous reading then it surfaces. I have tried 2 type of TWI approaches.

1. Using APP_TWI, I will get an internal error (code 3). Since I don't really need to use the scheduler, I tried to use the twi driver directly.
2. Using the TWI driver, I get an error code of (0x00008201) which I am unsure on how to even decipher it. Hopefully, someone can help me to unravel this issue.

best regards

[bjorn-spockeli]

The 0x00008201 error code corresponds to

DRV_TWI_ERR_ANACK	If NACK received after sending the address

The error codes returned by nrf_drv_twi_rx are documented on Infocenter, see this page. DRV_TWI_ERR_ANACK is defined as

#define 	DRV_TWI_ERR_ANACK   (PERIPH_DRIVERS_ERR_BASE + 0x0001)

where PERIPH_DRIVERS_ERR_BASE is 0x8200.