Custom I2C pins on STM32F103

[MDao.1]

Hello,

I would like to implement an I2C master on an STM32F103. It's pretty straightforward to select the IO's using cubeMX and to generate the code, but I don't want to use either of the available pins for I2C (PB7,PB6 or PB9,PB8). I need to use PB5 as SDA and PB4 as SCK. Is there a way to do this in cudeMX/cubeIDE without writing a custom I2C ?

Regards,

Mawaba.

[Peter BENSCH · Accepted solution]

No, this is not possible. In your case (I2C1) only the pins you mentioned can be selected.

BTW: with I2C2 you only have two pins, i.e. no alternatives.

When your question is answered, please close this topic by choosing Select as Best.

Good luck!

/Peter

[MDao.1]

Hello @Peter BENSCH​ ,

Thanks for the reply. I have a board here that is doing I2C on the same chip using PB5 & PB4. I do not have the source code and so I am trying to figure out how this could have been done.

Regards,

Mawaba.

[MDao.1]

Hello @Peter BENSCH​ ​ ,

Could I use those pins if I bit-banged I2C? If so are there any examples of i2c bitbanging for this chip?

Regards,

Mawaba.