How best to connect multiple memories

Question

Hi,I am working on a fairly complex setup. I have a need for a fair bit of SDRAM and also potentially a lot ofstorage. So i would like to use NAND FLASH. I also have some small QSPI memory for system profiles and firmware updates etc.My MCU is the STM32F746 216pin BGA.I have the SDRAM (IS42S32400F) connected as per the STM32F746GDISCOVERY. It uses 16 data lines connected directly to the FMC allowing access to half the RAM. This is OK for me as this is about 8MB.My question really relates to the NAND FLASH. An S34ML04G2 offering me 128MB on 16bit bus.How best to connect the NAND Flash? Do i also connect this to the FMC?If its possible to share the data lines, I suspect that it is from what i have read so far. I do see thos from page 73 of the STM32 datasheet that there arent enough pins to fully connect the NAND, I am unsure if the missing pins are just GPIO?Does anyone have a good example of a 16/32bit SDRAM and 16bit NAND flash on the same STM32?This is my first project of this magnitude using this size external memories, so im feeling my way through the dark.Any help would be most appreciated.

Tesla DeLorean · Answer

TSOP NAND parts are a long-term headache, seriously consider eMMC parts, basically solder down SD cards, and abstract all of the wear leveling and ECC stuff out of your codebase.

For NOR I'd definitely look to use QSPI, most likely 16-pin SOP 300mil, and double banked, as this is a form factor nearly everyone supports.

Yes, the F(S)MC interface shares pins, pull the schematics (user manual) to the EVAL series boards, the STM32756G-EVAL, for example

https://www.st.com/en/evaluation-tools/stm32756g-eval.html

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