Editing ANTIC (section)

== 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 uses [[Direct memory access|DMA]] to read a program called the [[display list]] which specifies these playfield features:
* 14 different graphics modes
** 6 character modes 
*** 4 types of font/glyph rendering
** 8 bitmapped 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|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 and GTIA|CTIA/GTIA]] to produce Player/Missile graphics (aka [[sprite (computer graphics)|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