Editing Commodore DOS (section)

== CBM DOS versions ==
At least seven distinctly numbered versions of Commodore DOS are known to exist; the following list gives the version numbers and related disk drives. Unless otherwise noted, drives are 5¼-inch format. The "lp" code designates "low-profile" drives. Drives whose model number starts with 15 connect via Commodore's unique [[Commodore bus|serial IEEE-488 bus (IEC Bus)]] serial (TALK/LISTEN) protocols; all others use the parallel [[IEEE-488]].
<!----------------->
<!-- We might consider making this bullet list into a table later. --Wernher -->
<!----------------->
* &nbsp; 1.0 &ndash; found in the [[Commodore 2040|2040]] and [[Commodore 3040|3040]] floppy drives
* &nbsp; 2.0 &ndash; found in the [[Commodore 4040|4040]] and [[Commodore 3040|3040]] floppy drives
* &nbsp; 2.5 &ndash; found in the [[Commodore 8050|8050]] floppy drives
* &nbsp; 2.6 &ndash; found in the [[Commodore 1540|1540]], [[Commodore 1541|1541]] including the one built into the [[Commodore SX-64|SX-64]], [[Commodore 1551|1551]], [[Commodore 2031|2031]] (+"lp"), and [[Commodore 4031|4031]] floppy drives
* &nbsp; 2.7 &ndash; found in the [[Commodore 8050|8050]], [[Commodore 8250|8250]] (+"lp"), and [[Commodore SFD-1001|SFD-1001]] floppy drives
* &nbsp; 3.0 &ndash; found in the [[Commodore 1570|1570]], external [[Commodore 1571|1571]], and [[Commodore 8280|8280]] floppy drives (8280: 8-inch), as well as the [[Commodore D9060|9060]] and [[Commodore D9060|9090]] [[hard disk|hard drive]]s
* &nbsp; 3.1 &ndash; found in the built-in 1571 drive of C128DCR computers
* 10.0 &ndash; found in the [[Commodore 1581|1581]] (3½-inch) floppy drive

Version 2.6 was by far the most commonly used and widely known DOS version, due to its use in the [[Commodore 1541|1541]] as part of [[Commodore 64|C64]] systems.

Note: The revised [[firmware]] for the 1571 which fixed the relative file bug was ''also'' identified as V3.0.  Thus it is not possible to differentiate the two versions using the version number alone.