External Flash + mass storage usb device (Firmware)

[Javier1]

Hello again dark electronics wizards.

I've been looking for some documentation about how to use an external flash memory with my stm32 designs.

Is there any magic way to do this? Or could anyome point me to the right way?

My goal is to add a qspi controlled flash chip instead of a sd card for my mass storage usb thing.

Many thanks in advance

Cheers

[Tesla DeLorean]

eMMC would be the way to go for speed.

QSPI NOR Flash is rather slow to erase and write, and the NAND would require a lot more block management and doesn't support execute-in-place.​

[Javier1]

@Community member​ what about the ease of integration?, i dont want to hard code the communication protocol.

Thats why so far my best candidate is an SD card hooked on the SDIO peripheral of my stm mcu.

[Tesla DeLorean · Accepted solution]

I've found eMMC to be relatively straight forward, uses mostly the same SDIO/SDMMC stack, but adds 8-bit width and DDR depending on the model.

The form factor is also consistent across manufacturers. There are socket versions used by some of the RPi clones, and also Nintendo.