STM32C0 RM0490 Rev 3 typo/bug: GPIOA_MODER reset value is not 0xEBFF FFFF

[KnarfB]

Hi,

I'm observing GPIOA_MODER reset value 0x2BFF FFFF on my STM32C0116-DK, not 0xEBFF FFFF as written in the RM.

My guess: because PA15 does not exist on that MCU 

hth

KnarfB

[Andreas Bolsch]

Indeed that seems to be the case for various devices, even when the corresponding hardware in physically present but not available due to bonding/packaging, see e.g.

https://community.st.com/t5/stm32-mcus-products/rm0455-stm32h7a-b-reset-state-of-syscfg-pmcr-incorrect/td-p/178787

Most probably the reset settings of many (all?) registers related to bonding/packaging options are not fixed in hardware, but programmed into the mysterious 'engineering bytes'  (along with calibration data) and copied into the corresponding registers upon reset. 

But here it might be even fixed in hardware, as for this particular die apparently there is no package with PA15. Would be interesting to know whether register bits, output driver etc. related to PA15 are present and functional, i.e. what happens if PA15 is configured to output and toggled. Is output state reflected in IDR?

 

 

[Simon.T]

Hello @KnarfB ,

 

PA15 is not present at all in STM32C011, so all things linked to this pin are not present. This is why you are seeing 0x2BFF FFFF instead of 0xEBFF FFFF. 

If you also check the GPIOB_MODER register it is exactly the same. 

 

Best regards,

 

Simon