nRF52840 twi drivers for ICM 20948 sensor data burst read

RE: nRF52840 twi drivers for ICM 20948 sensor data burst read

ovrebekk — Tue, 07 May 2019 14:03:22 GMT

Have you checked out the online documentation?

It is true that the examples still use the old driver, but the API of the new driver is quite similar, and you should be able to implement the same functionality without too many changes needed.

Best regards
Torbjørn

RE: nRF52840 twi drivers for ICM 20948 sensor data burst read

Coppers Copernicus — Mon, 06 May 2019 13:58:30 GMT

Dear ovrebekk,

Are there any examples for twi using the twim drivers ? all the twi examples in the SDK are using the nrf_drv_twi legacy drivers. pls guide me through thanks

RE: nRF52840 twi drivers for ICM 20948 sensor data burst read

ovrebekk — Mon, 29 Apr 2019 12:59:31 GMT

This sounds like a problem with your sdk_config.h file.

You need to enable the TWIM driver, and TWIM instance 0, in sdk_config.h for the macros and functions to be available.

If you are unable to make the right modifications to this file can you send it to me so I can have a look at it?

Best regards
Torbjørn

RE: nRF52840 twi drivers for ICM 20948 sensor data burst read

nikhilesh — Fri, 26 Apr 2019 08:29:46 GMT

thanks for the valuable suggestion dear ovrebekk. I changed all the instances from nrf_drv_twi.. to nrfx_twim.. now, i have the error

Error[Pe020]: identifier "NRFX_TWIM0_INST_IDX" is undefined .. in main.c

pls help how i resolve this..

RE: nRF52840 twi drivers for ICM 20948 sensor data burst read

ovrebekk — Thu, 25 Apr 2019 13:03:19 GMT

If you're starting out today you should definitely use the nrfx drivers, and for TWI master the best option is nrfx_twim.c.

nrfx_twi.c is kept for backwards compatibility with older parts like the nRF51 seires, while nrf_twim.c utilizes the new DMA enabled TWI master available in the nRF52 family.

0x11 corresponds to the NRF_ERROR_BUSY error, and often occurs if the driver is used in non-blocking mode, but is called as if it was blocking.

In non-blocking mode you will get an event in return once the current TWI operation is completed, and you have to wait for this event to occur before you can send or receive more data. If you try to call into the driver multiple times without waiting for this event you will get the busy error to tell you that the driver is currently busy with the current transaction.

Best regards
Torbjørn