CPU: Atari SALLY 6502 ("6502C")
Speed: 1.79 MHz, drops to 1.19 MHz when the TIA Television Interface Adaptor or RIOT (6532 RAM-I/O-Timer) chips are accessed
(note: Unlike a standard 6502, SALLY can be halted to allow other devices to control the bus)
RAM: 4 KB (2 6116 2Kx8 RAM ICs)
ROM: built in 4 KB BIOS ROM, 48 KB Cartridge ROM space without bankswitching
Graphics: MARIA custom graphics controller
160×240 (160×288 PAL) resolution or 320×240/288 resolution
25 color palette out of 256 colors (16 hues * 16 luma), different graphics modes restricted the number of usable colors and the number of colors per sprite
Direct Memory Access (DMA)
Graphics clock: 7.16 MHz
I/O: Joystick and console switch IO handled byte 6532 RIOT and TIA
Ports: 2 joystick ports, 1 cartridge port, 1 expansion connector, power in, RF output
Sound: TIA video and sound chip, same as the 2600. Only the sound is used in 7800 games. Both video and sound are used in 2600 games.
Optional POKEY sound chip on cartridge for improved sounds.