STM32F417 to STM32F437 - is the AF mapping identical for pins present in the 417?

[PHolt.1]

This previous thread refers

https://community.st.com/t5/stm32-mcus-products/stm32f4xx-does-going-up-a-package-pin-count-impact-pin-af/td-p/862282

The 437 is curiously a very close superset of the 417. Apart from the extra 64k RAM, the only difference is which ADC channel is used to read Vbat. And of course the device ID is changed. This makes the 437 a very easy and useful upgrade from the 407/417.

My Q is whether AF mapping is really identical, so that a 417 project can access the additional 437 peripherals (e.g. SPI4,5,6) by going to a larger pin count package.

Comparing the data sheets, it does not appear that the 437 gives you any new peripheral access without going to a larger package i.e. it does not offer any new AF flexibility. For example you cannot access SPI4-6 on the QFP100.

I am using the 437 for the extra 64k RAM. I check the device ID. This is 0x413 or 0x419 for the 417 or 437. If I detect the 437 I move the general stack 64k higher and fix up the Vbat measurement.

[TDK]

What does the data sheet say?

[Hal3]

And after you compare the data sheets, check the errata documents just in case there is some difference there.

[Sco]

To check the datasheet and compare the AFs directly will be a safe way for this topic.

[waclawek.jan · Accepted solution]

You could also compare the xml files from the "mcu" directory of your CubeMX installation, for the given two mcus.

JW

[PHolt.1]

That's clever :)

I don't have MX set up, however.

I had a look at the data sheets and AFAICT the 437 offers no mapping options above the 417, within a given package (in this case QFP100).

[waclawek.jan]

https://github.com/STMicroelectronics/STM32_open_pin_data

Enjoy! :‑)

(There's a conversion program at the STM32 part of my website which generates a cvs from these xml, importable to spreadsheet programs; but it's an .exe binary so I won't link to it here).

JW

[PHolt.1]

I have discovered an interesting thing on the 32F437: it has three more SPIs (total six) but only SPI4 is accessible on the QFP100 package, on Port E.

Option 1 is PE2 PE4 PE5 but you lose the ETH interface (PE2 is used for that) but SPI4 can also come out on PE12 PE13 PE14.

Together with this

https://community.st.com/t5/stm32-mcus-products/32f417-mapping-spi1-to-the-swd-debug-pins-pb3-pb5-how-can-this/td-p/864085

you can get a total of five SPIs in the QFP100 package.

[Andrew Neil]

@PHolt.1  You can also get a CSV report from CubeMX:

https://community.st.com/t5/stm32-mcus-products/stm32u535ve-pin-configuration-table-excel-or-csv-table/m-p/762005/highlight/true#M270645