This is the ill-fated successor to the Atari 800 8-bit computer. The 1200XL introduced several cosmetic and functional design changes including 64k of RAM, four programmable function-keys, a HELP key, and the elimination of two of the original four controller ports. Minor changes to the underlying operating system to support the new features resulted in compatibility issues with poorly-designed software. While Atari was quick to release a "translator disk" to mitigate these issues, the reputational damage was done. Consumers chose to continue purchasing the more compatible (and substantially cheaper) Atari 800, and Atari discontinued sales of the 1200XL a mere four months after its release. 1982 Atari Inc.
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arcade-museum.com
Argue if you will about the 1200XL being the black sheep of the Atari 8-bit line, the 1200XL was a major design and technical leap forward. Despite the exaggerated compatibility problems, this was the first of the XL-line that would surpass the aging 400/800 computers. Yes, the recessed joystick ports took some getting used to, and the re-designed cartridge port rendered some “fatter” cartridges unusable. However, its keyboard is arguably the best of the 8-bit era. There’s no question: this is my favorite Atari 8-bit computer and yes, it is also my very first home computer. Renewed interest by the current generation of vintage computer enthusiasts have greatly driven up the value of the “rare” 1200XL, and that feeling of vindication is long overdue!