A Disk Operating System (short: DOS) provides a software interface to magnetic disk-based storage. Commodore's Disk Operating System is built into the intelligent peripheral disk drive itself as firmware in ROM chips onboard.
Commodore DOS conforms to a standardized text command interface between the host computer and the intelligent peripheral.
Overview of a few DOS systems of different old home computer systems:
- CP/M (since 1975)
- TRS-DOS (1978)
- Commodore DOS/CBM-DOS (since 1979)
- Apple DOS (July 1978)
- Atari DOS (1979)
- AmigaDOS (1985)
- IBM-PC compatible DOS (since ca. 1980)
These DOS version and systems aren't compatible together!
- CBM2040 with CBM-DOS 1 (spring 1979)
- CBM3040 with CBM-DOS 1.2 (autumn 1979)
- CBM3040/CBM4040 with CBM-DOS 2.0 (1980)
- CBM4040 with CBM-DOS 2.1 (summer 1981)
- CBM-DOS 2.5 (1982)
- VC-1540/1541/1551, CBM2031/4031 with CBM-DOS 2.6 (since 1982)
- SFD-1001 mit CBM-DOS 2.7 (since 1983)
- 1570/1571 and CBM8020/9060/9090 with CBM-DOS 3.0 (since 1985)
- Inside 1571 in C128D/DCR with CBM-DOS 3.1 (since 1986)
- 1581 with CBM-DOS 10 (since 1986)
Notice: Later models of the same disk drive type can have higher CBM-DOS versions!
PC compatibles DOS
Overview of differents DOS for the PC from different software producers:
- MS-DOS from Microsoft
- PC-DOS from IBM (temporary developed by Microsoft)
- DR-DOS from Digital Research (to buy out by Novell)
- Novell DOS from Novell (a further development of DR-DOS)
- Caldera Open DOS (earlier: Novell DOS)
- FreeDOS (a open-free DOS clone)
In the years 1986 until 1988 a Italian programming team developed a MS-DOS Simulator, which are simulated important commands of the COMMAND.COM.