The Atari 2600, released in 1977, is the first successful video game console to use plug-in cartridges instead of having one or more games built in. It was originally known as the Atari VCS, for Video Computer System, and the name "Atari 2600" was first used in 1982, after the release of the more advanced Atari 5200. The 2600 was typically bundled with two joystick controllers and a cartridge game.
* CPU: MOS Technology 6507 @ 1.19 MHz
* Audio + Video processor: TIA. 160 x ~192 pixel, 128 colors, 2 channel mono sound.
* RAM: 128 bytes (plus up to 256 bytes built into the game cartridges)
* ROM (game cartridges): 4 KB maximum capacity (32 KB+ with paging)
* Input:
o Two screwless DB9 ¹ controller ports, for single-button joysticks, paddles, "trakballs", "driving controllers", 12-key "keyboard controllers" (0-9, #, and *) and third party controllers with additional functions
o Six switches (original version): Power on/off, TV signal (B/W or Color), Difficulty for each player (called A and B), Select, and Reset. Except for the power switch, games could (and did) assign other meanings to the switches. On later models the difficulty switches were miniaturized and moved to the back of the unit.
* Output: B/W or Color TV picture and sound signal (NTSC, PAL or SECAM, depending on region; game cartridges are exchangeable between NTSC and PAL/SECAM machines, but this will result to wrong or missing colors and often a rolling picture.)
(The screwless DB9 controller ports subsequently became the mechanical/electrical de facto standard for game controllers in the 8-bit and early 16-bit era, and was used in most subsequent Atari and Commodore consoles and home computers, among many others)
