Alternate Functions of STM32F429 & STM32F746 are different even though the Pin Configuration is the same?

[SMour.2]

Hi ,

I have a product in which I am using STM32F746 for LTDC. Now due to Chip Shortage, I had to use STM32F429 for the same product. However, even Though the Pins are same for both MCU's , The Alternate functions differ which creates lot of difficulties in Production. We have to change the PCB Design just for few tracks.

LTDC AF's do not match in both the MCU'S.

For example in STM32F746 PIN PA1 Is used for LTDC_R2 but same alternate function is not available in STM32F429 for the same pin.

Is there any way of matching the Alternate Function for both the devices?

[TDK]

The AFs are coded in hardware and can't be changed.

There are significant differences between these chips anyway, such as an entirely different cortex core. You're not going to be able to just substitute one with another.

[S.Ma]

No full IO cross bar mux here, so drop in replacement requires precheck befofe selecting a part.