ABC 800 explained

Type:Personal computer
Releasedate:1981
Cpu:8-bit Zilog Z80A @ 3 MHz
Graphics:Text mode 80×24 colour Teletext, 78×75 block graphics or,, with red, green, blue, yellow, cyan, magenta, white and black
Sound:Beep, within the keyboard
Os: ROM for BASIC II
Memory: ROM + RAM
Connectivity: DE-9, 4680 bus connector,,
Manufacturer:Luxor in Motala, Sweden
Price: (ex.VAT)[1]

The Luxor ABC 800 series are office versions of the ABC 80 home computer.[2] [3] [4] They featured an enhanced BASIC interpreter,[5] a slightly faster clocked CPU and more memory: 32 kilobytes RAM and 32 KB ROM was now standard, the Z80 is clocked at (quarter the 12 MHz crystal). It featured 40×24 text mode with eight colors (ABC 800 C) or 80×24 text mode monochrome (ABC 800 M). They could also be extended with "high" resolution graphics (240×240 pixels at 2) using RAM as video memory.

Models

ABC 800

The ABC 800 came in a monochrome version with amber text on a brown background with an 80 character wide screen, and a color version with 40 characters. The main board is integrated with the keyboard, much like the Amiga 500. However, the ABC computer has a very sturdy metal chassis.

Storage is usually two 5.25" floppy disk units in 160, 320 or 640 KB capacity. External hard disk systems became available later (primarily the ABC 850 with 10 MB). Model numbers 'ABC 800 M' for monochrome and 'ABC 800 C' for color.

Luxor advertising asked, "Who needs IBM-compatibility?" However, most computer buyers eventually considered it a requirement. A certain degree of compatibility between the ABC and IBM PC platforms could be achieved with the help of a program called 'W ABC'.

The ABC 800 computer was also sold by Facit under the name Facit DTC.

ABC 802

The ABC 802 is a compact version with 64 KB RAM where 32 KB is used as a RAM disk. The main board is integrated with a 9" CRT screen and has improved graphics, though no high-resolution graphics. Luxor ABC 802 was a model with a small monochrome screen in yellow phosphor, intended for offices. Here with two 5.25 inch disk drives along the side of the display. The grey-brown color was common for all ABC 800 (and ABC 1600) products and was different from the beige ABC 80.

ABC 806

The ABC 806 is a version with main board, screen (DA-15) and keyboard (DIN-7) as separate units. It has RAM where is used as a RAM disk, as well as more advanced 512x240x16 graphics.

Performance

In order to see how the ABC 800 would compare to other contemporary personal computers, in 1982, the Swedish magazine MikroDatorn used the Rugg/Feldman benchmarks of eight short BASIC programs (BM1 - BM8) defined by the American Kilobaud Magazine and routinely used by the British magazine Personal Computer World for testing new machines.

The result was that ABC 800's semi-compiling BASIC interpreter turned out to be faster than most other BASICs used in popular machines, especially when integer variables are used, the results for some well known computers were as follows (times in seconds):

BM1 BM2 BM3 BM4 BM5 BM6 BM7 BM8 ABC 800 (integer) not measured - see ABC 80 for approximate numbers ABC 800 (single precision) 0.9 1.8 6.0 5.9 6.3 11.6 19.6 29 ABC 800 (double precision) 1.2 2.2 10.0 10.6 11.0 17.8 26.4 144 IBM PC 1.5 5.2 12.1 12.6 13.6 23.5 37.4 35 Apple III 1.7 7.2 13.5 14.5 16.0 27.0 42.5 75 VIC-20 1.4 8.3 15.5 17.1 18.3 27.2 42.7 99 ZX81 in "fast mode" 4.5 6.9 16.4 15.8 18.6 49.7 68.5 229

As seen from the table, the ABC 800 was approximately twice as fast as the IBM PC on floating point calculations, except for BM8 where it was only 20% faster. Using integer variables (only measured for the older ABC 80 in this test) the numbers would be approximately 2-3 times as low (i.e. speeds 2-3 times as high) as for the single precision results in the table.

ABC 800 character set

ABC 800 character set, as described on the user manual[6]

ASCII codeCharacter ModeGraphic ModeASCII codeCharacter ModeGraphic ModeASCII codeCharacter ModeGraphic ModeASCII codeCharacter ModeGraphic Mode
3256880PP104h
33!57981QQ105i
34"5882RR106j
355983SS107k
3660<84TT108l
37%61=85UU109m
38&62>86VV110n
39´63?87WW111o
40(64ÉÉ88XX112p
41)65AA89YY113q
4266BB90ZZ114r
43+67CC91ÄÄ115s
44,68DD92ÖÖ116t
45-69EE93ÅÅ117u
46.70FF94ÜÜ118v
47/71GG95--119w
48072HH96é120x
49173II97a121y
50274JJ98b122z
51375LL99c123ä
52476NN100d124ö
53577MM101e125å
54678NN102f126ü
55779OO103g127

See also

Notes and References

  1. Web site: empty. 091209 pc-museum.com
  2. Web site: Luxor ABC 800 series . oldcomputers.com.
  3. Web site: Rautiainen . Sami . 2020 . Luxor ABC 800 serie . 2023-09-10 . www.devili.iki.fi.
  4. Web site: RigPix Database - Vintage home computers (Except IBM PC's and their clones) - Luxor ABC-800 . 2023-09-10 . www.rigpix.com.
  5. Web site: Starring the Computer - Luxor ABC 800 . 2023-09-10 . www.starringthecomputer.com.
  6. Web site: Rautiainen . Sami . 2020 . Luxor ABC800 Käyttöohje: Liitteitä - Näppäinkoodit merkki/grafiikkamuodossa (ASCII-taulukko) . Welcome to my home.