No I2C Clock signal after Restart Condition

[uli stone]

Hello,

I raised this problem in another topic I posted, but it is with another title and I'm not sure I will get there the help (title might be missleading).

I have the problem after sending Slave Address and Register Address and creating a start condition I don't get any clock signal from the STM32F4 microcontroller.

Hoch can I solve this?

Thank you

[Mon2]

Hi @uli stone​ . Sorry to jump in the middle of this dialog but is it important for you to use a step-by-step I2C handshake with your project? For example, why not apply the very powerful DMA feature of the I2C port using one of the working examples from CubeMX, etc. ? Most of the time, such examples can be working in a few minutes. The STM32F4 is very powerful and offer interrupt / DMA use to quickly send / receive data over I2C bus. You can also follow the examples to build an I2C slave using one of the kits.

[Danish1]

If the I2C peripheral won't do it, then it presumably thinks it has reason not to do it.

Here's where it becomes something of a detective-game. You need to collect all the clues.

What I eventually had to do to sort out my I2C code was - whenever I was about to write to a control register - log the I2C status register(s), the time in microseconds, where I was in my code and what I was just about to do.

Those figures in the reference manual show master-read and master-write, with what events should happen to trigger each next step in your code. Sadly they don't show master-write-restart-read, or what might indicate failure so you can abort without waiting forever.