RE: Twi interface

Simon — Tue, 30 Jul 2019 14:01:35 GMT

The "abstraction flow" for accessing the twi peripherals (and the other peripherals) in SDK 15.x.x is the following:

TWI driver (Legacy layer) → TWI driver (NRFX) → TWI HAL

The Legacy TWI driver is a glue layer that remaps to the NRFX functions (see this link for an explanation how it works)
- It is not pure remapping, some functionality is added in between
The NRFX TWI driver accesses the HAL driver, and makes it more simple to use the TWI HAL
The TWI HAL accesses the TWI registers directly

Unless you need complete control and flexibility of what you are doing I would not recommend you to use the TWI HAL, as it requires a lot of extra work. Regarding the choice of driver, there has been some discussion about this. However, I would recommend you to use the TWI driver, since all the examples in the SDK uses this and I think it will be less to troublesome. Also the legacy driver is more compatible with BLE functionality.

In the sdk_config.h file, you should use the legacy definitions and ignore the NRFX definitions, as explained here.

Best regards,

Simon

RE: Twi interface

yashchabria — Tue, 30 Jul 2019 13:51:18 GMT

I sorted the 'NRF_DRV_TWI_INSTANCE_0' issue with sdk_config.h

RE: Twi interface

yashchabria — Mon, 29 Jul 2019 15:35:56 GMT

Also, what does this imply 'NRF_DRV_TWI_INSTANCE_0' was not declared , I have enabled TWI in sdk_config.h