Atom
Atom

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Info
   
Setname:  atom   
Year: 1979
Manufacturer: Acorn
Status: good  works
Type: Home Computer
Clones: Atom with BBC Basic,
Atom with Eprom Box
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 ("ic22")cpu 1000000 Hz
Speaker ("mono")audio
Filtered 1-bit DAC ("speaker")audio
Screens
Screen ("screen")raster horizontal 320 x 240 @ 50.000000
Media devices
floppydisk ("floppy0") floppydisk1 flop1 dsk, 40t, fdi, td0, imd, cqm, d77, d88, 1dd
floppydisk ("floppy1") floppydisk2 flop2 dsk, 40t, fdi, td0, imd, cqm, d77, d88, 1dd
cassette ("cassette") cassette cass wav, tap, uef
quickload ("quickload") quickload quik atm
cartridge ("cartslot") cartridge cart bin, rom
RAM options
2K 2048
4K 4096
6K 6144
8K 8192
10K 10240
12K 12288
32K 32768
Software lists
atomoriginal

 Optional hardware: (available with specific slot configurations)

 Configure the slot options for atom:
 Slot Value
 centronics 
 


Show detailed info about 'Configurations' of this system
Configurations

NameValue
Artifacting Off
 Standard
 Reverse


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

NameValueCompatible device(s)
centronics ap2000ap2000
 covoxcovox
 covox_stereocovox_stereo
 ex800ex800
 lx800lx800
 lx810llx810l
 pl80comx_pl80
 printer centronics_printer

Romset info
ROM NameSizeCRC32SHA1Dump StateBIOS option
abasic.ic208192 289b77910072c83458a9690a3ea1f6094f0f38cf8e96a445good
afloat.ic214096 81d86af7ebcde5b36cb3a3344567cbba4c7b9fde015f4802good
dosrom.u154096 c431a9b771ea0a4b8d9c3caf9718fc7cc279f4306a23b39cgood
Sysinfo



Features


* CPU: 6502 1 MHz
* Co-Processor: 6847 Video Display Generator, PIA 8255 (keyboard & tape)
* RAM: 2 KB (up to 12 KB, or 32 KB using external RAM expansion kit.)
* VRAM: 6 KB
* ROM: 8 KB (Atom BASIC and COS), up to 16 KB
* Text Modes: 32 x 24 / 16 x 12
* Graphics Modes: 64 x 64 (4 colors), 64 x 96 (4 colors), 128 x 96 (monochrome), 64 x 192 (4 colors), 128 x 192 (2 colors), 256 x 192 (monochrome)
* Colors: 8
* Sound: Built-in beeper
* I/O Ports: Tape interface, UHF Modulated TV output, Acorn Bus Extension
* Keyboard: QWERTY, full-stroke keyboard, 60 keys, ESC, BREAK, COPY, DELETE, CTRL, RETURN, LOCK, SHIFT (x2), REPT, arrow keys (x2)
* Built In Language: Basic, machine-code


Usage


MESS currently supports two different Atom configurations:

* atom [Acorn Atom]: the base version of the computer
* atomeb [Acorn Atom with Eprom Box]: the expanded version with the additional ROMs

Both drivers allows to load cassette tapes in .wav format, through the "cassette" (cass) device, and disks images in .ssd format through two floppy drives, corresponding to "floppydisk1" (flop1) and "floppydisk2" (flop2).

Also notice that a "quickload" (quik) feature is present for .atm files and that the "printer" (prin) is supported as well.

Keyboard

This system requires 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, full-stroke keyboard, 60 keys

ESC 1! 2" 3# 4$ 5% 6& 7' 8( 9) 0 -= :* UP BREAK

LEFT
RIGHT COPY Q W E R T Y U I O P @ \ DELETE


DOWN CTRL A S D F G H J K L ;+ [ ] RETURN


LOCK SHIFT Z X C V B N M ,< .> /? SHIFT REPT


SPACEBAR


Known Issues


The original location of the 8271 memory mapped registers is 0xa00-0x0a04. (This is the memory range assigned by Acorn in their design.) This is in the middle of the area for expansion RAM. Many Atom owners thought this was a bad design and have modified their Atom's and dos rom to use a different memory area. The atom driver in MESS uses the original memory area. (from the source)


History and Trivia


The Acorn Atom was the ancestor of the BBC computers series. It was sold in kit or ready-assembled versions.

The great advantage of the Atom compared to its competitors (TRS-80 & PET), was its high resolution capabilities (256 x 192) which were quite unusual in 1979 for the price.

The built-in BASIC was in some ways quite limited (it could only use integers for example) but an optional 4K ROM added the ability to use floating point numbers, trigonometric functions, to convert degrees/radians and to draw graphics in color. More add-ons were also available enabling autonumbering, a faster cassette interface (1200 bauds), and functions such as INKEY$, MID$, READ, DATA, FILL, etc...
There was even a BBC BASIC board available.

A lot of applications were available on sideways ROMs that plugged into the "utility ROM socket" as Acorn called it, such as the "Atom Word Pack ROM" (word processing) or Atom-Calc (a 4K ROM spreadsheet).

A colour card was available, connected to the BUS connector, it provided 8 colors, 4 simultaneously at the 64 x 192 resolution or 2 at 128 x 192 for example. But it was known to overheat!

A lot of other peripherals were developed :
* a 5.25" floppy disk drive (100K) which held the DOS in a 3K ROM but cost about twice as much as a new Atom!,
* a digital-tape recorder,
* a printer interface,
* a network card called EcoNet which enabled linking of up to 250 Atoms (210 K/Bauds transfer rate),
* RAM expansions.

(info from old-computers.com)


Links


* Acorn Atom Projects -- http://www.howell1964.freeserve.co.uk/Acorn/Atom/Atom.htm
* Atom Review -- http://home.wanadoo.nl/hhaydn/index-e.html
* Atom user guide -- http://members.aon.at/~musher/bbc/essentials.htm
* Oh no, not another computer museum! -- http://www.xs4all.nl/~fjkraan/comp/
* Un-official ACORN ATOM Home Page -- http://www.users.globalnet.co.uk/~thoth/atom/atom.htm
* Acorn Atom at old-computers.com -- http://old-computers.com/museum/computer.asp?c=80


Other Emulators


* Acorn Atom Emulator (win) -- http://www.homepages.hetnet.nl/~wouterras/atom.htm
* Acorn Atom Emulator (*nix) -- http://www.iwriteiam.nl/Ha_Atom.html
* ATOMAC (mac) -- http://www.p-skids.freeserve.co.uk/#Atomac



Edit the History info for this game.

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