Stm32f105 SPI3 change pins

[coolname]

I am running a simple poc to test the SPI connection to a flash memory chip. When I select SPI3 in cube MX, It gives me two options for the set of pins. I would like to use PC12 as Clock but it wont let me change it. Hand editing the generated code doesn't seem to take any effect. There are so many pins available why is it not letting me assign to any unused pins?

Is there a right way to modify the pins after code is generated?

[RhSilicon]

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There are so many pins available why is it not letting me assign to any unused pins?

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SPI3 is a hardware module, it has specific pins that can be alternated.

[FBL]

Hello @coolname and welcome to ST Community,

Could you please specify the full part number? 

You need to refer to the datasheet to check the related pins physically mapped according to the package being used.

Connectivity line, ARM®-based 32-bit MCU with 64/256 KB Flash, USB OTG, Ethernet, 10 timers, 2 CANs, 2 ADCs, 14 communication interfaces (st.com)

For further details, please refer to the reference manual section 9.3.11 SPI3/I2S3 alternate function remapping and section 9.4.2 AF remap and debug I/O configuration register (AFIO_MAPR)

Thanks for selecting Accept as solution if this helps!