I2C error handling

[ECost]

I am developing with STM32F030Cx, using CubeMX for the configuration. The application is basically a simple full cooperative scheduler (no RTOS, no context switching) that calls several "tasks" in a sequence. I am using the blocking functions of the HAL I2C driver.

STM32 I2C will work in master mode only.

I would like some directions on how to handle the communication errors (BERR, ARLO, timeout etc.) or to reference material such as a flow chart or source code of a library or RTOS.

Maybe the handling of these errors is simple and it is only a matter of following the reference manual, but while researching for questions/answers on the subject, I saw some messages on the I2C channel hanging when a BERR occurred and the fix required some workarounds. So, I would appreciate some advice on how to do to guarantee my application is capable of self recovering when some of these errors occur.

Thanks in advance.

[ECost]

As a follow-up, I have implemented a recovery routine based on your suggestions above, along with some tips of answers in the link below:

https://electronics.stackexchange.com/questions/267972/i2c-busy-flag-strange-behaviour

In the end I disable the I2C interface using HAL_I2C_DeInit, perform the bus reset and restart the I2C using HAL_I2C_Init.

I have set a second Discovery to inject errors on the I2C bus. The error gen inject pulses on SDA and SCL at regular intervals while the main routine reads the slave continuously. I monitor the bus activity with the protocol analyzer and the errors are displayed. When a timeout is detected, the recovery routine is called. I left it running overnight and after around 12 million iterations it recovered from more than 500k timeouts and 13k AF errors. These were the errors I observed when I used the tweezers to inject errors.

Thank you for your help.

As it is not true if it does not have a picture... :grinning_face:

[toroid]

For my application, HAL_I2C_DeInit and HAL_I2C_Init worked fine as I2C error handler.

[ECost]

Toroid, thank you for your suggestion.