* System
o 6502 8-bit CPU
+ 3 Registers (A, X, Y), plus PC, SP, and flags.
+ 56 Instructions
+ 64K Address Space
o 64K RAM
o 8K Basic ROM
o 8K Kernel ROM
* Display
o Character Map Mode
+ Each character is 8x8. The screen is made of 40x25 characters.
+ Character Set Source: ROM (predefined), or RAM (programmable)
+ Standard Character Mode: Any one color, or the screen background color
+ Multicolor Character Mode: Any one color, two pre-selected colors, or the screen background color
+ Extended Background Color Mode: Any two colors.
o Bitmapped Graphics Mode
+ HiRes Mode: 320x200 pixels, any one color per character-cell, and the background color
+ Multocolor Mode: 160x200 pixels, 3 pre-selected colors, any one color per character-cell, and the background color
o Sprites
+ 8 sprites available, 24x21 pixels per sprite.
+ Standard Mode: Any one color overlayed on the background display.
+ Multicolor Mode: Any one color, plus 2 pre-selected colors overlayed on the background color.
o Other Features
+ Smooth scrolling (both horizontal and vertical)
+ Selectable Display Border Color
o Output
+ NTSC (to a TV)
+ Luma/Chroma (to a monitor)
* Sound
o 3 voices mixed at one master volume.
o Available waveforms
+ Sawtooth
+ Triangle
+ Square Wave
+ Noise Waveform
o Envelope Control
+ Attack
+ Decay
+ Sustain
+ Release
o Filtering
+ High-pass
+ Bandpass
+ Low-pass
+ Notch reject
o Other Features
+ Vibrato
+ Ring Modulation
* I/O
o Built-in
+ Keyboard
o Options
+ Cassette Drive
+ Floppy Disk Drives (5.25" - 1541/1571)
+ Hard Drives (MFM)
+ Joysticks (Atari 7-pin standard)
+ Cartridge Port (direct access to CPU bus)