LSI ASIC dedicated to generating 2D computer graphics to be shown on a television screen or computer display

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Article URL: https://en.wikipedia.org/wiki/ANTIC Comments URL: https://news.ycombinator.com/item?id=28368410 Points: 2 # Comments: 0
This article is about the Atari 8-bit display chip. For the magazine, see Antic (magazine) . For the surname, see Antić . For the London pub chain, see Antic Collective

Atari ANTIC microprocessor on an Atari 130XE motherboard

Alphanumeric Television Interface Controller[1] (ANTIC) is an LSI ASIC dedicated to generating 2D computer graphics to be shown on a television screen or computer display. Under the direction of Jay Miner, the chip was designed in 1977-1978 by Joe Decuir, Francois Michel, and Steve Smith[2] for the Atari 8-bit family of home computers first released in 1979 and was patented by Atari, Inc. in 1981.[3] ANTIC is also used in the Atari 5200 video game system released in 1982, which shares most of the same hardware as the 8-bit computers.

ANTIC is responsible for the generation of playfield graphics which is delivered as a datastream to the related CTIA/GTIA chip. The CTIA/GTIA provides the coloring of the playfield graphics, and is responsible for adding overlaid sprites referred to as "Player/Missile graphics" by Atari.

Atari advertised it as a true microprocessor, in that it has an instruction set to run programs (called display lists) to process data. ANTIC has no capacity for writing back computed values to memory, it merely reads data from memory and processes it for output to the screen, therefore it is not Turing complete.

Features [ edit ]

The list below describes ANTIC's inherent hardware capabilities meaning the intended functionality of the hardware by itself, not including results achieved by CPU-serviced interrupts or display kernels frequently driving register changes.

ANTIC uses DMA to read a program called the "Display List" controlling these Playfield features:

14 different Playfield graphics modes 6 character modes 4 types of font/glyph rendering 8 map modes

Output a variable number of blank scan lines

Playfield Text and Map modes can be mixed onscreen

Variable screen height up to vertical overscan

Horizontal and…
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