Atari 400 (NTSC)
Atari 400 (NTSC)

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Info
   
Setname:  a400   
Year: 1979
Manufacturer: Atari
Status: good  works
Type: Home Computer
Clones: Atari 400 (PAL)
Emulation info
   
Overall emulation:  good   
Color emulation:  good  
Sound emulation:  good  
Graphics emulation:  good  
Savestates:  unsupported   

Tech info
 Base hardware: (available in all slot configurations)
Chips
M6502 ("maincpu")cpu 1789790 Hz
POKEY ("pokey")cpu 1789790 Hz
Speaker ("mono")audio
POKEY ("pokey")audio 1789790 Hz
DAC ("dac")audio
Screens
Screen ("screen")raster horizontal 336 x 225 @ 59.923329
Media devices
floppydisk ("fdc:floppy0") floppydisk1 flop1 atr, dsk, xfd
floppydisk ("fdc:floppy1") floppydisk2 flop2 atr, dsk, xfd
floppydisk ("fdc:floppy2") floppydisk3 flop3 atr, dsk, xfd
floppydisk ("fdc:floppy3") floppydisk4 flop4 atr, dsk, xfd
cartridge ("cartleft") cartridge cart bin, rom, car
BIOS options
default OS Rev. B
reva OS Rev. A
RAM options
48K 49152
Software lists
a800_floporiginal
a800original
xegsoriginal

 Optional hardware: (available with specific slot configurations)

 Configure the slot options for a400:
 Slot Value
 sio 
 


Show detailed info about 'Configurations' of this system
Configurations

NameValue
Television Artifacts Off
 On


Show detailed info about 'Slot Options' of this system
Slot options

NameValueCompatible device(s)
sio cassettea8sio_cass

Romset info
ROM NameSizeCRC32SHA1Dump StateBIOS option
co12399b.rom2048 6a5d766e01a6044f7a81d409c938e7dfde0a1af5832229d2good
co12499b.rom4096 d818f3e8bcdec2188f6a6a5bfc1df4e383bd828d34b5c4acbaddumpdefault
co14599b.rom4096 c1690a9bc5248e8565574fd39ae1c3f4f356aa4cac07df95baddumpdefault
co12499a.rom4096 29f64e17abf7ec488c6b600f1b7f30bdc7f8a2bf6a727675baddumpreva
co14599a.rom4096 bc533f0ce217148495fa747fe5488132d8d22533e68c7e58baddumpreva
Sysinfo



Features


* CPU: MOS 6502 1.79MHz
* Co-Processors: ANTIC (Scrolling, Sprites, Video), CTIA / GTIA (Color, Sprites, Collisions), POKEY (Timers, Sound, Keyboard, Serial I/O), PIA 6810 (I/O including controller ports)
* RAM: 8K or 16K (newer models)
* ROM: 10K
* Display: 24 x 40 text, 320 x 192 monochrome, 160 x 96 with 128 colors
* Expansions: 2 internal expansion slots, 1 cartridge slot under front cover and a daisy-chainable expansion bus
* Ports: 4 controller ports
* Keyboard: QWERTY membrane keyboard with 61 keys, 4 function keys (Reset, Option, Select, Start)
* TV video output
* Storage: external 5.25" floppy drive, cassette recorder
* OS: Atari OS


Usage


Currently, MESS supports the following Atari 400 versions:

* a400 [Atari 400 (NTSC)]
* a400pal [Atari 400 (PAL)]

Both drivers support cart dumps in .rom and .bin format, using the "cartridge" (cart) device, and up to four floppy drive for disks in .atr, .dsk and .xfd format, "floppydisk1" (flop1) to "floppydisk4" (flop4).

Keyboard

These systems require full keyboard emulation to work correctly. At startup, full keyboard emulation mode is enabled by default. Whilst in full keyboard emulation mode, some key associated functionality may be disabled (like the ESC key for EXIT). The keyboard emulation mode is toggled using the "Scroll Lock" key (by default).

Original Keyboard: QWERTY, 61 keys plus 4 function keys on the right

CLEAR INSERT DELETE SYSTEM
ESC 1! 2" 3# 4$ 5% 6& 7' 8@ 9( 0) < > BACK S BREAK RESET

CLF SET UP _ DOWN |
TAB Q W E R T Y U I O P - = RETURN OPTION

LEFT \ RIGHT ^ CAPS
CTRL A S D F G H J K L ;: + * LOWR SELECT


SHIFT Z X C V B N M ,[ .] /? ATARI SHIFT START


SPACE

Keys "TAB", "-", "=", "+" and "*" have 3 functions.


Known Issues


Most disk and cartridge images should work, though some graphic issues may exist. Note that the Atari 400 has less memory than the Atari 800, and some disk images may not work as a consequence; this is not a bug in the emulation.


History and Trivia


The Atari 400 and 800 were the first home computers to use custom coprocessors and the first to use "sprites" and special video interruptions like display lists, features that will be implemented several years after on the Commodore Amiga. It offered high graphic resolution, lots of colors and great sound capabilities, more than other computers could do then! The two models had same characteristics, the 400 is the low-cost version, it has only 16 KB (instead of 48 KB), one cartridge port (two for the 800) and a membrane keyboard (a typewriter style keyboard one for the 800).

Originally, the 400 was sold with 8 kb RAM, but later most 400's with 16 kb.

The Atari 400 was known inside Atari as code name "Candy".

(info from old-computers.com)


Links


* Atari 400 at the Atari Hystory Museum -- http://www.atarimuseum.com/computers/8BITS/400800/400/400.html
* Atari 400 at vintage-computer.com -- http://www.vintage-computer.com/atari400.shtml
* Atari 400 at old-computers.com -- http://www.old-computers.com/museum/computer.asp?c=76


Other Emulators


* Atari800 (Unix, Amiga, MS-DOS, Atari TT/Falcon, SDL, WinCE) -- http://atari800.sourceforge.net/
* Atari++ -- http://www.math.tu-berlin.de/~thor/atari++/
* Atari800Win Plus -- http://www.a800win.atari-area.prv.pl/
* Rainbow (historical) -- http://www.chrislam.co.uk/
* PC Xformer (historical) -- http://www.emulators.com/xformer.htm



Edit the History info for this game.

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