Embedded Transaction filesystem (ETFS)

The limits for ETFS are:

Filename length
91 bytes
Pathname length
1024 bytes
File size
2 GB − 1; 32-bit filesystem limit
Maximum number of files
32768 (15 bits)
Default maximum number of files
Max cluster size
Maximum filesystem size
64 GB

For NAND flash, some additional limitations apply:


For ETFS on NAND, you can perform 1-bit software error correction coding (ECC) for the data in the spare area. Support configurations are available for:

Once calculated, the spare area receives the ECC value from devio_postcluster(), and then writes it to NAND flash. To determine the appropriately sized ECC value, use the following:

To take advantage of the spare area, you'll need to make the following changes for BSPs: