2M (DOS)
2M is a DOS program by the Spanish programmer Ciriaco García de Celis. It enables higher than normal capacity formatting of floppy disks. It saw active development from 1993 to 1995. The last version, v3.0, was released on March 6, 1995. It was written in C and assembler and compiled using Borland C++ 3.1.
The program consisted of two major components: 2M and 2MGUI. Of these, 2M was the main program enabling the formatting, reading and writing of high density 3.5" disks formatted to a capacity of either 1804 KiB or 1886 KB, and 2MGUI was a proof-of-concept program that demonstrated the ability to format any normal high density 3.5" disk to a capacity of over two million bytes (1972 KB) on any disk drive. Both programs implemented disk I/O speedups in the form of "Sector Sliding" and "DiskBoost", which work on the principle of ordering the physical sectors on the disk to facilitate pauseless reading over track changes.
| Formatting program | 5.25", DD | 5.25", HD |
|---|---|---|
| FORMAT (40/80 tracks) | 368,640 bytes (360 KB) | 1,228,800 bytes (1200 KB) |
| FDFORMAT 1.8 (82 tracks) | 839,680 bytes (820 KB) | 1,427,456 bytes (1394 KB) |
| 2MF 3.0 /F (82 tracks) | 839,680 bytes (820 KB) | 1,511,424 bytes (1476 KB) |
| 2MF 3.0 /M (82 tracks) | 923,648 bytes (902 KB) | 1,595,392 bytes (1558 KB) |
| 2MGUI 1.0 (82 tracks) | 1,000,064 bytes (976 KB) | 1,679,104 bytes (1639 KB) |
| blank disk (82 tracks) | ~1,025,000 bytes (1001 KB) | ~1,708,224 bytes (1668 KB) |
| Formatting program | 3.5", DD | 3.5", HD | 3.5", ED |
|---|---|---|---|
| FORMAT (80 tracks) | 737,280 bytes (720 KB) | 1,474,560 bytes (1440 KB) | 2,949,120 bytes (2880 KB) |
| FDFORMAT 1.8 (82 tracks) | 839,680 bytes (820 KB) | 1,763,328 bytes (1722 KB) | not supported |
| 2MF 3.0 /F (82 tracks) | 1,007,616 bytes (984 KB) | 1,847,296 bytes (1804 KB) | 3,694,592 bytes (3608 KB) |
| 2MF 3.0 /M (82 tracks) | 1,091,584 bytes (1066 KB) | 1,931,264 bytes (1886 KB) | 3,862,528 bytes (3772 KB) |
| 2MGUI 1.0 (82 tracks) | 1,204,224 bytes (1176 KB) | 2,019,328 bytes (1972 KB) | 4,038,656 bytes (3944 KB) |
| blank disk (82 tracks) | ~1,230,000 bytes (1201 KB) | ~2,050,000 bytes (2002 KB) | ~4,100,000 bytes (4004 KB) |
See also
- DMF, a high-density diskette format used by Microsoft
- fdformat, a similar program that offers less capacity
- XDF, a high-density diskette format used by IBM
References
- All information is based on that given in 2M-INFO.EXE supplied with 2M v3.0