!!!How to find the OS Version of your computer !!For ATARI 400 and ATARI 800 Computers In Atari BASIC type the following command if you have an 400/800 %%prettify {{{ PRINT PEEK(65528) }}} /% and press the RETURN key ||Value||OS Version |221|400/800 OS Rev. A NTSC |214|400/800 OS Rev. A PAL |243|400/800 OS Rev. B NTSC |34|400/800 OS Rev. B PAL (DOES THIS VERSION ACTUALLY EXIST? see [Rarity 10]) !!For ATARI XL and XE Computers If you have an XL or XE Computer, type %%prettify {{{ PRINT PEEK(65527) }}} /% and press the RETURN key ||Value||Version |10|XL/XE OS Rev 10 |11|XL/XE OS Rev 11 |1|XL/XE OS Rev 1 |2|XL/XE OS Rev 2 |3|XL/XE OS Rev 3 |59|XL/XE OS Rev 3B (Arabic) |4|XL/XE OS Rev 4 see also [How to find the revision number of Atari Basic]