ECC Media Filesystem (EMFS) is a filesystem with an ECC feature based on Extended Hamming (511, 502) code. This 12-bit version is specifically designed for floppy disks. Please note that this project is a proof of concept (POC), and its future may involve incorporation into another project.
- Add support for directories
- Develop a filesystem checker (utilizing ECC for checking and fixing)
- Implement variable node size (currently fixed at 512 bytes)
- Implement compression (Consider using a custom algorithm; if a custom algorithm is chosen, develop it as a separate GitHub project)
- General code & struct cleanup (May break already formated drives)
- Create a Linux driver (to be developed as a separate GitHub project)
This POC is targeted to manipulation with raw image files. In case of Linux you can actually use it on devices like /dev/sd* or /dev/fd*.
For file system (FS) manipulation, use the following command (with read used as an example):
./read IMAGE FILEFor FS creation, the syntax is as follows:
./mkfs IMAGE [FS_LABEL] [FS_SIZE_IN_NODES] [CUSTOM_BOOT_CODE]This filesystem, ECCMediaFS12 (EMFS12), offers several distinctions from the traditional FAT12 file system. Below is a comparison table:
| Feature | FAT12 | EMFS12 |
|---|---|---|
| Compression | ❌ | ❌ (Not added yet) |
| ECC | ❌ | ✔️ |
| File dates & times | ✔️ | ❌ |
| Long File Names support | ✔️ | ❌ |
| Variable cluster/node size | ✔️ | ❌ (Not added yet) |
| Volume boot record | ✔️ | ✔️ |
| Directory size | fixed to fit in cluster | fixed to fit in node |
| Root directory size | 224* | fixed to fit in node |
| Free Space | 1 457 664 bytes | 1 439 000 bytes |
| Directory entries per 512 bytes | 16 entries | 28 entries |
| Filesystem Type | File Allocation Table | Node chain |
Notes:
- Both file systems were tested on media with a size of 1 474 560 bytes (floppy disk).
- FAT12 used in this comparison was formatted with a cluster size of 512 bytes, and other values were kept in default.
- *Value can be modified during formatting.
Conclusion: EMFS12 introduces ECC support compared to FAT12. While FAT12 supports features such as file dates & times, long file names support, and variable cluster sizes (not yet implemented in EMFS12), EMFS12 focuses on data integrity.
This project is licensed under the GNU AGPLv3.
- Special thanks to ChatGPT for helping me with creating this README.md.
- With updates that break already formated drives may or may not came out FS conversion program.