Connect internal microSD card to SPI interface.

[dreieck]

Ahoj,

I have a VoCore2 Ultimate (bought October 2022), and I have flahes a stock OpenWRT 23.05.0-rc3.

I want to expand the internal storage without a microSD card sticking out. Physically, there is space within the case to put a microSD card, and to solder it to some of the free pins.

I thought of directly using the SPI interface and use the SD-card in SPI mode with `kmod-mmc-spi`.

Is this (likely) going to work, or is the SPI interface not really usable for that desire?

In that case, software SPI-mode on the GPIO pins needs to be used with `kmod-spi-gpio`, I think.

And can the uBoot directly boot from that, or (how) would I need to modify the bootloader? (A workaround can also be to use OpenWRT "extroot" mount, but that is less "clean" solution for me.)

Has anyone already done something like this?

If this also does not work I also could solder the microSD card to the microSD card slot pins, but this would render the external microSD slot useless, and it would be nice to retain the ability to just add a microSD card to share some files or so.

Regards!

[Vonger]

maybe this can be reference: https://vonger.cn/?p=14685