Replace SD Card with EMMC

Build threads
1

Are there any code changes required in ProffieOS to implement an eMMC in place of an SD card slot on a Proffieboard V3.9? From some limited research, it seems that a eMMC chip with SPI quad I/O interface should be compatible.

This chip, for instance:

https://www.winbond.com/resource-files/W25N02KVxxIRU_Datasheet_20210625_G.pdf

It seems like the connections would be the same on the board:

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I wanted to ask before going too far down the path. I know there was some discussion about using eMMC on the (now dead) Proffieboard M2 thread a few years ago.

Also, can we format the eMMC via the Proffieboard USB port, or does that have to be done before it is soldered?

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First of all, that’s not an eMMC chip, it’s an SPI flash chip.
While it may be technically possible to use it, it would need software changes which are not easy.

Second, the M2 is not dead, merely resting. It uses a chip which acts exactly like an SD card, yet, it is also not an eMMC chip.

eMMC is a lot like an SD card, but the eMMC standard got rid of SPI compatibility. That means it wouldn’t work with a V2 proffieboard. However, it may work with a V3 board, because the V3 boards uses SDIO, not SPI to talk to the SD card. I would have to read up on it to be sure, but I think it should work.

Formatting can be done through the “mass storage” interface.