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Alphanumeric Television Interface Controller (ANTIC) is a 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 for Atari 8-bit computers released in 1979 and was patented by Atari, Inc. in 1981. ANTIC is also used in the Atari 5200 video game system release in 1982. 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 separately moveable, overlay graphics, that is, sprites also known as "Player/Missile graphics" on the Atari. Atari advertised it as a true microprocessor, in that it has an instruction set to run programs (called display lists) to process data. Nonetheless 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 == 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 Reads via DMA and executes 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 Vertical coarse scrolling * Identify sections of the display subject to Horizontal and/or Vertical Fine scrolling * Trigger a CPU-serviced interrupt routine, called the "Display List Interrupt", at specific scan lines (also called "raster interrupt" or "Horizontal Blank Interrupt" on other systems) * Trigger a CPU-serviced interrupt routine, called the "Vertical Blank Interrupt", at the end of the display frame. Other Register-based functions: * Variable screen width up to horizontal overscan * Define the distance of movement for Horizontal and Vertical Fine scrolling * Provides real-time information of the electron beam's vertical screen location. * Reads a light pen horizontal/vertical coordinates (CRT only) * Soft, re-definable character set. * Adjustable display of inverse video characters. * Characters may be vertically reflected. * Control the display-oriented Vertical Blank and Display List interrupts, and the Reset key interrupt. * Performs DMA for CTIA/GTIA to produce Player/Missile graphics (aka sprites) * Non-fixed RAM. This allows RAM for graphics features to be located almost anywhere in the 16-bit memory address range. This applies to: * * Display lists. * * Playfield Graphics data * * Character set fonts * * Player/Missile Graphics data 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ANTIC」の詳細全文を読む スポンサード リンク
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