STM32F4xx - does going up a package pin count impact pin AF mapping?

[PHolt.1]

I think it doesn't have an impact and you just get extra pins (e.g. extra SPI controllers becoming accessible) if going say 100 to 176. But it's not clear...

IOW, will existing code run exactly as before?

Isn't the silicon identical and they merely bond out the extra pins on the bigger packages?

[TDK]

If the part number is the same except for the package, yes the AF mapping will be identical. This is covered in the datasheet. One AF mapping table for the entire family.

[Issamos]

Hello @PHolt.1 

I think if both MCUs have the same sub device name (F401, F407,..) (same datasheet) the AF should not be changed and the same code (made for the smallest package) should run on both MCUs. For different subfamilies, I think more verification is needed.

Best Regards.

II

[mƎALLEm]

Hello;

" does going up a package pin count impact pin AF mapping?" -> Absolutely not.

All packages of the same part number have the same die inside. Common GPIOs between the different packages have common AFs. Extra GPIOs have more AFs, more SPI AFs, TIMs AFs, etc ..