nrf52832 executing TWI function from app_timer handler

RE: nrf52832 executing TWI function from app_timer handler

David — Thu, 11 Jan 2018 12:57:45 GMT

Thank you for your explanation.

RE: nrf52832 executing TWI function from app_timer handler

MartinBL — Thu, 11 Jan 2018 10:20:18 GMT

Hi,

NRF_LOG_FLUSH() is a blocking function and if you are using UART as backend this is using interrupts while printing messages. Hence, you are triggering interrupts from within an interrupt context and this might cause priority issues. If you are using RTT as backend it will not use interrupts the same way, but since NRF_LOG_FLUSH() is blocking and since it takes a significant amount of time to format a string you should never flush in an interrupt context. NRF_LOG_FLUSH() is intended to be used only in main context.

RE: nrf52832 executing TWI function from app_timer handler

David — Thu, 11 Jan 2018 07:54:38 GMT

I found out what was the issue. It was a call to NRF_LOG_FLUSH() inside one of the function in the interrupt handler. Why the LOG FLUSH causing that ?

RE: nrf52832 executing TWI function from app_timer handler

David — Thu, 11 Jan 2018 07:21:12 GMT

Thanks for your answer. I2C works out of the interrupt handler. Currently i would like to solve my issue and not try other i2c drivers.

RE: nrf52832 executing TWI function from app_timer handler

Nguyen Hoan Hoang — Wed, 10 Jan 2018 23:26:49 GMT

Does the I2C works outside of interrupt ? Make sure the I2C works first then use it in timer interrupt.

You can also try the I2C driver from EHAL. It's a lot simpler and can be used in interrupt. There is an use case example from this blog https://devzone.nordicsemi.com/blogs/1223/writing-ble-firmware-with-a-few-lines-of-code-part/

RE: nrf52832 executing TWI function from app_timer handler

David — Wed, 10 Jan 2018 18:47:15 GMT

yes , i do know.

RE: nrf52832 executing TWI function from app_timer handler

Julie H — Wed, 10 Jan 2018 18:21:51 GMT

Just to get this out of the way, you do know that "bigger number" means "lower priority", right?