(c) 2024 Earle F. Philhower, III earlephilhower@yahoo.com
This library implements a static wear-leveling FTL algorithm suitable for use on embedded systems with SPI flash. Using static wear leveling should help extend the useful life of flash memory, especially when combined with the FAT filesystem which has certain high-write usage areas such as the FAT tables and directory entries.
There were three design goals:
- Preserve data
- Keep the flash array within a limited PE (program/erase) cycle range
- Miimize the memory at the cost of write speed
While the process used here is similar in concept to what a modern SSD does, this is definitely not a general purpose SSD FTL layer. It is missing things like bad block handling, parallelism, short-circuit paths, data retention scans and rewrite, and much more. It is also limited to 16MB of flash and erase pages of 4KB for memory and expediency considerations.
An implementation for the Arduino-Pico RP2040 core as well as a NBD (Network Block Device) plugin is included. Porting to other architectures should only require developing a small FlashInterface subclass.
This software is provided on an AS-IS basis and no comes with no warranties. See LICENSE.md for the full GNU LESSER GENERAL PUBLIC LICENSE.