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13.7) Which versions of the Operating System (OS) are there?

This section written by Freddy Offenga, mailto:offen300@hio.tem.nhl.nl

The following Operating Systems exist for the Atari 8-bit:

Rev.   System(s)   Models    Size   Part Nr(s)
~~~~~~ ~~~~~~~~~~~ ~~~~~~~~~ ~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A      NTSC        400/800   10kB   CO12499B, CO14599B, 12399B (*)
A      PAL         400/800   10kB   CO15199, CO15299, CO12399B
B      NTSC        400/800   10kB   (?)
B      PAL         400/800   10kB   (?) (*)
1 A    NTSC/PAL    1200XL    16kB   CO60616A, CO60617A
1 B    NTSC/PAL    1200XL    16kB   CO60616B, CO60617B (?) (*)
1      NTSC/PAL    600XL     16kB   CO62024
2      NTSC/PAL    XL/XE     16kB   CO61598B
3      NTSC/PAL    XE        16kB   C300717
4      NTSC/PAL    XEGS      16kB   C101687

(?) more information or confirmation required

(*) these versions should exist, although I've not seen them.
    If you have one (or more?) of these, please contact me.

NOTE:
The 400/800 O.S's consist of three ROMs (two 4kB and one 2kB).