FDCAN ROM bootloader pins for stm32H743ZI

[Javier1]

As discussed in here, im trying to use ST\s ROM bootloader, when i read AN2606 Page 280 shows the FDCAN1 rx and tx Pins 

Those pins dont exist in stm32H743ZI

@KDJEM.1 proposed "you can activate the FDCAN bootloader with only by PH13/PH14 pins." 

What does "activate" mean?, those pins dont exist

[Andrew Neil]

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@Javier1 wrote:

What does "activate" mean?, those pins dont exist

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I guess he means those are the only pins you can use.

The stm32H743ZI datasheet says:

"The boot loader is located in non-user System memory. It is used to reprogram the flash
memory through a serial interface (USART, I2C, SPI, USB-DFU)."

So no mention of FDCAN:

https://www.st.com/resource/en/datasheet/stm32h743zi.pdf#page=27

So it looks like you can't use the bootloader via FDCAN on this chip.

PS:

Similarly for STM32H750VB:

https://community.st.com/t5/stm32-mcus-embedded-software/fdcan-bootloader-for-stm32h750vb/m-p/762446/highlight/true#M59030

[Javier1]

"The boot loader is located in non-user System memory. It is used to reprogram the flash
memory through a serial interface (USART, I2C, SPI, USB-DFU)."

I believe those are just examples, immediatly after that , the datahseet refeers to the AN2606


So this table 119 page 280 from AN2606 is an error?

also table 3 page 39

[Andrew Neil · Accepted solution]

Looks like they've been over-general with their "STM32H74xxx".

Needs to add a note, "Where these pins are available"

@STTwo-32 @STOne-32 @KDJEM.1 

PS:

Also Table 1:

PPS:

Another example where this caused confusion:

https://community.st.com/t5/stm32-mcus-products/fdcan-bootloader-on-ufbga169-stm32h743ai/td-p/577760

[Javier1]

apparently we spotted an error in ST documentation, time to buy more (and different) nucleo boards
https://community.st.com/t5/stm32-mcus-products/fdcan-bootloader-on-ufbga169-stm32h743ai/m-p/762474#M270765

[KDJEM.1]

Hello @Javier1 @Andrew Neil ,

As mentioned in AN2606, for STM32H74, the FDCAN bootloader pins are PH13 and PH14. So, if the PH13 and PH14 pins are not available in some packages, the FDCAN bootloader is not supported. 

The LQFP100, TFBGA100, LQFP144, and UFBGA169 STM32H743 packages do not have PH13 and PH14 pins, so the FDCAN bootloader is not supported.

Thank you @Andrew Neil and @Javier1 for reporting your feedback about the AN2606 application note. I reported internally your suggestion internally.

Note that, also I reported internally the datasheet typo for correction.

Thank you for your contribution in STCommunity.

Internal ticket number: 200567  (This is an internal tracking number and is not accessible or usable by customers). 

Kaouthar