The Atari 800 is the big brother of the Atari 400. With a beige plastic case, the machine is more compact than the Atari 400. Atari designed the machine to accept two cartridges at one go; usually SLOT A was for basic cartridge. The 800 was the only 8 bit machine with two cartridge design. The design was identical to the Atari 5200 except that the cartridge ports and controllers are different. The cartridges where protected under a plastic door. When the plastic door is open the machine switches off for protection. Behind the cartridge slot, there is a hidden panel with four slots. The first slot holds the ROM, Graphics chips, colour encoder and clock generator, while the other three hold combinations of 8KB or 16KB memory modules. Atari designed this system for future upgrades, and for changing the display board when the machine was shipped to other countries like France, Italy etc. In fact the French version (SECAM) could only benefit from a palette of 16 colours instead of the 128 Colours.
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| 800 U |
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| US$ 700 1979 later price reduced every year. |
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BK016120063
A1551018299 |
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| 1979 & 1981 |
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| 6502A @ 1.79Mhz (NTSC) or 1.77Mhz (Pal/Secam) |
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| 10KB Rom for hardware operations Basic Rom comes in cartridge format. Primary in 1979 released with 8KB but after a year was released 16KB. By 1982 the ram was expanded to 48KB. Memory cards where released in 8KB and 16KB. The cartridge sockets where referred as Left and Right with different pin signals. |
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| Medium beige plastic compact case with a plastic protective door for cartridge and expansion. When the door is opened the machine will automatically switched off. The keyboard is a standard US QWERTY keyboard and four orange/light brown function keys. |
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The Atari 800 display capabilities are handled by Atari’s famous graphics processor. The ANTIC is a microprocessor which fed data to the GTIA crt controller chip. Pre 1982 models used the CTIA controller which are compatible. The difference between the two, are three extra modes and a few small differences in sprite timing. Also the CPU can access directly the GTIA bypassing the ANTIC which slowed the machine alot. On the other hand the ANTIC was capable of different display modes on different scanlines and horizontal and vertical scrolling. The GTIA is capable of displaying a maximum of 256 colours (16 colour hues with 16 different level of brightness), and provides eight sprites, four playes and four missiles with sprite collision detection. Note that SECAM version was unable to display 256 colours. The ANTIC display capabilities are as follows: 40×24 with 2 colours, characters are rendered in an 8×8 matrix. 256 characters are available with the top 128 characters are inverse versions of the first 128. Text mode at 40×19 with 2 colours, characters are rendered in an 8×10 matrix, and supports true descenders like ‘g’ which drop below the baseline. The 2 colour text mode are two different luminance levels of one hue. Text Mode 40×24, 40×12, 20×24 and 20×12 all with 5 colours support. Graphics mode 80×48,160×96, 160×192, 320×192 with 2 colours (last graphic mode two different luminance levels of one hue). Graphics Mode 40×24, 80×48, 160×96 and 160×192 all supports 4 colours. The following modes are only supported with GTIA processor installed. Graphics Mode 80×192 with 16 colours (16 luminances of one hue or all 16 hues at one luminance), and 80×192 with 9 colours.
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| The sound chip codenamed POKEY was capable of four channels with 8-bit pitch resolution (256 tones), and 16 different volume levels. It is also possible to combine channels in pair to form two 16 bit channels or 65536 tones. Sound is output thru the TV rf modulator or through the Monitor socket. The chip is also responsible for user input devices, timers and data flow. A fifth channel is available to produce clicks when the keyboard is in use but its output is through an internal speaker. |
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4 x Joystick ports,
2 x Cartridge ports capable of supporting 8KB per cartridge. 4 x Expansion slots for ANTIC, GTIA or CTIA board, and the other three for memory boards. Expansion connector located at the back end of the main board. SIO Serial In/Out interface for Atari Cassette recorder at 300bps disk drives, printers and modems. The I/O is very flexible capable of rates up to 125 kbps. TV output and Composite Video and Audio out connectors for connecting TV and Monitor. |
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| Standard 9V AC 750mA. A DC power supply does not work since the AC signal is needed to generate TV Raster |
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| Dimensions 410mm x 320mm x 115mm (W x L x H) Weight Approx 3.5Kg |
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