This article covers the peripherals available for Atari's8-bit computer family, which includes the 400/800, XL, XE, and the XEGS. Because the Atari 400/800 8-bit computers included an RF modulator, stringent FCC regulations limiting radio emissions applied. Consequently, the Atari 400/800 systems internal construction used large metal frames as Faraday cages to prevent emissions. This prevented the use of plug-in internal cards to add connections for peripherals. To permit easy expansion, Atari developed the SIO bus. This bus daisy chains together all Atari peripherals into a single string—disk drives, printers, modems, RS-232 interfaces. Since only one kind of connector plug is used for all devices, the Atari computer was easy for novice users to expand. Devices on the bus have their own IDs and peripherals can deliver downloadable drivers to the computer during the boot process. However, the additional electronics in these "intelligent" peripherals made them cost more than the "dumb" devices used by other systems.
Both the names and styling of Atari's 8-bit peripherals generally matched the current computer range at the time they were released. Thus, they can be divided into one of three groups- those corresponding to the 400/800 era, the XL era and the XE era respectively. These are superficial issues; the majority of peripherals listed here will work with any 8-bit Atari computer. In addition to those listed below, Atari failed to release a large selection of machines and peripherals that were otherwise completed.
400/800 era (1979-1982)
410 Program Recorder - a tape drive, 600 bit/s on compact cassettes
* There exist several variants of the 410. Early models were larger due largely to a much larger speaker area at the back, and had square cornered buttons. Later versions were smaller and had buttons that were rounded off on the front.
* The 410 used stereo with the data recorded on one track and the other track holding audio that could be fed through the 400 or 800's sound output. The tape could also be programmatically stopped and started, provided the 'Play' button was engaged.
810 Disk Drive - a 5¼" floppy disk drive, single-density single-sided, 90 KB
* Pre-1982 drives "have notoriously poor speed regulation", ANALOG Computing reported in 1983; unlike other companies, "ATARI did not begin incorporating a reliable separator into the 810 until early 1982".
820 40-Column Printer - dot matrix on adding machine paper
822 Thermal Printer - 40-column thermal on slightly wider paper
825 80-Column Printer - dot matrix, used the Centronics interface so required an 850
830 Acoustic Modem - a 300-baud modem, using an acoustic coupler, used RS-232 so required an 850
850 Interface Module - included four RS-232 ports and one Centronics parallel port
CX30 Paddle Controllers - a set of 2 potentiometers attached to a single Atari joystick port. Originally released with the Atari VCS console.
CX40 joystick - 8-directional 1-button joystick, originally released with the Atari VCS console. Bundled with some Atari 400/800 packages and also sold separately. Originally all-black, a version with a matching gray base was later bundled with the Atari XEGS.
1090 XL Expansion System - a case connected to the PBI port, with 5 slots intended for various expansion cards
XE era (1985 onwards)
XEP80 Interface Module - provides 80-column display and a Centronics parallel interface for a printer, controlled by NS405, an 8048 based chip. Attached via a joystick port controlled at 15625 baud horizontal video timing.
XC11 Program Recorder - a tape drive
XC12 Program Recorder - a tape drive. It was based on an earlier tape drive, Phonemark PM-4401A, not manufactured by Atari. A number of similar models, not marketed by Atari were released, mainly in Eastern Europe and Latin America. These included:
