DOS – Which Version is loaded

 

Sometimes it can be helpful to know which DOS you booted with. With one or two PEEKs from BASIC
you can easily find out. Use this table to determine the DOS version:


PEEK( )      Value        DOS Version
           Returned

3889          0          SpartaDOS 2.3e
              13         DOS 4.0
              15         SpartaDOS 1.1
              19         Atari DOS 2.5
              76         Atari DOS 3.0
              78         Atari DOS 3.0
              89         SpartaDOS 3.2d
              108        MYDOS 4.0
              207        OSS OS/A+ 4.00
              221        MYDOS 4.50
              238        OSS DOS XL 2.3
              244        Atari DOS XE

1804          0          OSS DOS XL 2.3
              124        Atari DOS 2.0s


Just type PRINT PEEK(3889) [RETURN] at the READY prompt in BASIC, and compare the number printed
on your screen with this chart. Note that Atari DOS 3.0 may return either a value of 76 or 78 at
location 3889. Both Atari DOS 2.OS and OSS DOS XL 2.3 show a value of 238 at location 3889. To
distinguish between the two, check location 1804.