Which pins are usable on the F429 Discovery (DISC1) board?

[Lars Beiderbecke]

Posted on December 31, 2017 at 10:32

I'm using the STM32F429 Discovery Board. Comparing to the Nucleos, most pins seem to be used by peripherals.

I disabled those peripherals I don't need (e.g., LCD, USART, ...) to free some pins, but I found some pins (e.g., PB13) are still used by some peripheral (i.e., they interfere with my logic), although they show as free in CubeMX.

Is there a list of pins that are reserved for the board itself even when all peripherals are disabled?  I know about LEDs and button, but what about ST Link and others?

There is some official diagram of both pin headers which categorizes all pins into 'without conflict' and 'connected to other components' (

https://os.mbed.com/platforms/ST-Discovery-F429ZI/

 ). I don't understand this list. Is this the answer to my question, or are they talking about conflicts between two or more peripherals (of which some are not shown in the diagram)?#pins

[Tesla DeLorean]

Posted on December 31, 2017 at 15:59

If I didn't need the screen I'd physically remove it.

Consider perhaps the STM32F469I-DISCO, expansion options there are via the Arduino header and the SDRAM is bigger (16MB vs 8MB). They used a 216-ball BGA so are less pin constrained, and it has a 128Mb QSPI NOR.

http://www.st.com/en/evaluation-tools/32f469idiscovery.html

 

Executing code from SDRAM is about 6x slower based on previous experiments. (I've posted previously on FLASH vs SRAM code execution, and also code run from SDRAM. Tip: Don't put the stack in SDRAM, it will slow everything)

[Lars Beiderbecke]

Posted on December 31, 2017 at 16:10

Thanks for the suggestions, I'll give it a try.

[Bogdan Golab]

Posted on December 31, 2017 at 16:48

There is a CSX pin discribed in the LCD controller manual (mentioned earlier) - to disable IL chip. MAybe it will put the IL pins in high impedance state...

[Bogdan Golab]

Posted on December 31, 2017 at 17:05

What we need is to make LCD invisible from the electrical perspective so we want to either remove it (as Clive One suggested) or put its interfaces in high-impedance state.

[Lars Beiderbecke]

Posted on January 01, 2018 at 10:30

Yes, I see, thanks.  I guess it'll be easier to just get a Nucleo or the Discovery that Clive suggested.

[Bogdan Golab]

Posted on January 01, 2018 at 14:59

I prefer 'soft' solutions because I have hardware engineering background