Micro SD card slot specs

[tkbay]

Hi all -

What kinds of cards are compatible with the Micro SD card slot?  SD/SDHC/SDXC?
Are there any memory size or speed class rating limits?

Thanks

[digistump]

Any card that can work in SPI mode (backwards compatible MMC mode) - which rarely stated on the card - but generally most cards do. All SD should - SDHC/SDXC don't have to but more often than not seem to.

Memory size support would be a function of the library you are using - I imagine most support up to 32gb minimum.

Speed doesn't play much of a role since we are using the SPI protocol to access them

[erix]

Hi,

I have an additionnal question about the cards we can use in the SD card slot.
what kind of format must we use? fat etc etc?
Thanks in advance
Regards
Erix

[digistump]

That is completely up to the library you are using - see the arduino reference for the built in library here: http://arduino.cc/en/Reference/SD