Nucleo-144 F756ZG

[hockeymikey]

Summary

Adds the Nucleo-144 F756ZG variant board. https://www.st.com/en/evaluation-tools/nucleo-f756zg.html

Validation

Tested on the board I had and blink ran fine. Would be great for someone to just double check my work since it's my first rodeo.

[fpistm]

Hi @hockeymikey
Thanks for the PR.

[ABOSTM]

Hi @hockeymikey,
Thanks for this PR.
Globally that fine, nevertheless few remarks:

• Can you please run Astyle to format code
• There is a missing part : declare the new board in board.txt file
  see https://github.com/stm32duino/wiki/wiki/Add-a-new-variant-(board)#8---declare-the-variant
• also see inline comments

[ABOSTM]

Hi @hockeymikey ,
Thanks for this update.
There are some remarks that are still valid:

• variant.h

Chip STM32F756ZG has 8 sectors and Flash base address of last sector is 0x080C0000
Also update comment : 1MB of flash

• PeripheralPins.c

It looks like you mixed with some F767:
On F756 PA_15 doesn't have UART7 alternate function.
... this is the original one:
https://github.com/stm32duino/Arduino_Tools/blob/master/src/genpinmap/Arduino/STM32F7/STM32F756ZGTx/PeripheralPins.c

      This is valid for UART, SPI, CAN and QUADSPI arrays.

[ABOSTM]

Hi @hockeymikey ,
I take the liberty to continue your Pull Request, specially to merge the support of NUCLEO_F746ZG #999 which is very similar to NUCLEO_F756ZG and can use the same variant.
The only difference between both is that F756 embed cryptographic accelerators AES and CRYP, that are not currently supported by Arduino.

[ABOSTM]

Hi @hockeymikey ,
I don't know what you intend to do, but it looks like variant.cpp has duplicated code, and the same for variant.h.

[fpistm]

@hockeymikey
I've made a mistake while updating your PR.
I've sync your dork master with the original repo that's why this PR was closed automatically.
Anyway, I've submitted the clean PR in #1014.