Editing Atari 5200 (section)

===Differences from Atari 8-bit computers===
[[David H. Ahl]] in 1983 described the Atari 5200 as "a 400 computer in disguise".{{r|ahl1983spring}} Its internal design is similar to that of Atari 8-bit computers using the [[ANTIC]], [[POKEY]], and [[GTIA]] coprocessors. Software designed for one does not run on the other, but source code can be mechanically converted unless it uses computer-specific features. ''[[Antic (magazine)|Antic]]'' magazine reported in 1984 that "the similarities grossly outweigh the differences, so that a 5200 program can be developed and almost entirely debugged [on an Atari 8-bit computer] before testing on a 5200".<ref name="converting" /> [[John J. Anderson]] of ''[[Creative Computing]]'' alluded to the incompatibility being intentional, caused by Atari's console division removing 8-bit compatibility to not lose control to the rival computer division.<ref name="anderson198403">{{cite news | url=https://archive.org/stream/creativecomputing-1984-03/Creative_Computing_v10_n03_1984_Mar#page/n51/mode/2up | title=Atari | work=Creative Computing | date=March 1984 | access-date=February 6, 2015 | author=Anderson, John J. | page=51|quote=The games division [..] saw the home computer division as a threat [..] If any of their new machines could expand into true computers, the reins would automatically be handed over [..] To the games division, this was a fate worse than death [so] they chose death. [The 5200 was internally] very nearly an Atari 800 [but] all compatibility and expandability had been designed out [..] If, in 1981, the next-generation game machine ''had'' been designed to be compatible with the Atari 400 and 800 microcomputers, Atari would not be in the state it is today. Instead, the 5200 game unit was launched. Internally, it was very nearly an Atari 800, and as such was a fabulous game machine. The notable exceptions were that all compatibility and expandability had been designed out [..] with an external keyboard and 800 compatibility, could have been transformed into a product superior to the famed Coleco Adam, way back in 1982.}}</ref>

Besides the 5200's lack of a keyboard, the differences are:<ref name="converting">{{Cite magazine |last=Buchholz |first=Claus |date=January 1984 |title=Transporting Atari Computer Programs to the 5200 |url=https://archive.org/stream/analog-computing-magazine-15/Analog_Computing_15_1984-01_Inside_the_600XL#page/n59/mode/2up |magazine=ANALOG Computing |page=59}}</ref>
* The [[Atari 8-bit computers#Built-in operating system|Atari computer 10&nbsp;KB operating system]] is replaced with a simpler 2&nbsp;[[kilobyte|KB]] version, of which 1&nbsp;KB is the built-in character set.
* Some hardware registers, such as those of the GTIA and POKEY chips, are at different memory locations.
* The purpose of some registers is slightly different on the 5200.
* The 5200's analog joysticks appear as pairs of [[Paddle (game controller)|paddle]]s to the hardware, which requires different input handling from the digital joystick input on the Atari computers

In 1987, [[Atari Corporation]] released the [[Atari XEGS|XE Game System]] console, which is a repackaged 65XE (from 1985) with a detachable keyboard that can run home computer titles directly,<ref>{{cite web | last = Harris | first = Neil | title = Re: Is Atari killing the 8 bit? | date = May 12, 1987 | url = http://groups.google.ca/group/comp.sys.atari.8bit/msg/98a62e383f31d6cc?dmode=source | access-date = June 5, 2014| institution = [[Atari Corporation|Atari Corp.]] | quote=So what we have with the XE Game System is essentially a 65XE in disguise. [..] It is completely compatible with the current 8-bit line, including software.}}</ref> unlike the 5200.<ref name="converting" /> Anderson wrote in 1984 that Atari could have released a console compatible with computer software in 1981.{{r|anderson198403}}