Replacing SD card with external flash (Photon to P1)


Hello All,

We are in the process of transferring from Photon to P1. On the code we are running we use the SdFat library, but now we have switched over to external flash this library is not longer suitable.

I have seen another post on this forum referring to using the SPIFFS library, but our chip is a Serial NAND flash memory and the other forum post referred to NOR memory. Anyway that library doesn’t seem to be working.

Is there a NAND flash memory library that you guys can recommend? Will FatFs library be suitable? The specific chip we are using is W25N01GVZEIG.


Okay. So having done a bit more research I’ve found that NAND doesn’t work great with a Fat file system.

Are there any other file system libraries more compatible with NAND memory, or would I need to build this from scratch?

I’ve heard to not use FatFs with NAND because of a lack of wear leveling and bad block handling. How serious is this? Which would be easier to implement, a new filing system (such as YAFFS, JFFS2, UBI/UBIFS or UFFS) or using FatFs with NAND despite the potential issues.

I will only be storing binary files on the memory, and then uploading these files via FTP.

Can anyone offer some advice on the best route to proceed with?