DAI Personal Computer
AY-3-8910 | |
Connectivity | Parallel port, RGB video out, RS232c, DCE bus, cassette tape (600 bauds), stereo audio out |
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The DAI personal computer[1][2][3][4] is an early home computer from the Belgian company Data Applications International.[5][6][7] The DAI came to market in 1980.[8] It provided many pioneering features such as high resolution color graphics, a maths co-processor, and a pre-compiling BASIC interpreter. However, it never became a commercial success.
Contemporary reviews noticed the lack of application packages, with the computer appealing more for programmers.[9]
History
The computer was initially designed by DAI for the UK subsidiary of Texas Instruments for use with the PAL televisions used in Britain.[10] Texas Instruments US did not want to build a PAL version of their TI-99/4A home computer, although they subsequently authorized one after they saw the DAI.[11][8]
The Dutch educational TV broadcast company
In France the machine sold for 1300 Fr by November 1981, 1365 Fr by November 1982 and 1021 Fr by September 1983.[1]
The machine was also used to create graphics for TV programmes in the early 1980s.[14]
After DAI filed for bankruptcy in 1982, InData (a Prodata spin-off)[3] continued producing and selling the machine up to 1984.[5][8][1]
Main technical specifications
The DAI was based on a very early 8-bit
Graphics capabilities with 48k RAM installed allowed up to 528 x 240 pixels in 4 out of 16 color palette in 4 successive blobs, leaving 16k programming space. The graphics modes were controlled by a device called Programmable Graphics Generator (Thomson EF9369 graphics chip), implementing several techniques:
- decoupling physical scan linesfrom the 'logical' lines. The repeat count of physical scan lines could be 0 to 15 per line (Due to interlacing a physical scan was two pixels high),
- configurable horizontal resolution per line,
- using indexed colors,
- limit modifying the color palette to one color per line.
In 4 color mode, per logical line one foreground and one background color could be selected, so each line element or logical pixel could be represented by one bit.
In 16 color mode, the color palette was inherited from the previous line. Only one of the four usable colors could be changed.
These graphical limitations were handled by
The
This technique was rare (only other known examples are the
To enhance the mathematical abilities of BASIC, (and assembler programs) an
The first working example was produced in less than 3 months, by 3 people, one of whom was taping up the circuit board layout. All 64K of assembler was the work of one man David Collier, and all the hardware design the work of another David, David Lockey. The original decision to use the 8080A 1 MHz processor (already in use by DAI on other products) was forced by the timescale, which itself was dictated by a desire to show the machine to a TI USA board meeting. In the end, only a flight on a Concorde got the machine there on time. However, the slow CPU dictated a huge amount of work on the pre-compiling BASIC and the option for hardware-assisted floating point which might not have been required if the newer Z80 had been chosen.
The decision to design the PC to use any old off-the shelf cassette tape recorder made the load and save speeds slow. The need to keep the end-user cost down dictated the need for extra complexity to output a TV signal capable of working with a domestic TV. When Texas Instruments finally did put the 99/4 onto the European market a few months later, it was initially sold only in a pair with an American NTSC TV because it could not drive European PAL and SECAM sets.
Further technical details
- CPU: Intel 8080A at 2 MHz
- Memory: a maximum of 48 kB dynamic RAM, 24 kB ROM and 256 Bytes of static RAM (stack RAM)
- Keyboard: 56 Keys
- Video: EF9369,[15] PAL compatible UHF CH 36 color-TV (antenna) output signal with audio
- Text mode: 60 characters × 24 lines (66 characters per line supported)
- Graphics modes: Low - 88 x 65 pixels; Medium - 176 x 130 pixels; High - 352 x 260 pixels; Very high - 528 x 240 pixels (non-square)
- available colors: 4 or 16 colors (16 color mode was actually 4 color palette)
- Sound generation: 3 frequency generators + 1 noise generator (General Instrument AY-3-8910?)
- Game controllers: 2 input interfaces for paddles or joysticks(DIY). Each can control three 0-5V inputs and a switch.
- Storage: 2 separate audio-cassette interfaces, using a cable for data INPUT/OUTPUT and START/STOP switch, (600 Baud)
- Alternative main storage systems:
- Memocom MDCR-D, Mini Digital Cassette Recorder (which used Philips minicassettes)
- Two 5.25 inch floppy disk drives, 2 x 180K (which enabled the use of CP/M).
- Memocom MDCR-D, Mini Digital Cassette Recorder (which used Philips
- Compatible with optional card rack, the ("DAI Real World Card System"), control system.
- I/O Connectors:
- Serial port RS-232, DB-25 female.
- 2 audio-cassette ports, 2 x 6 pin DIN female.
- Parallel port DCE-Bus, DAI proprietary 3 x 8 bit parallel port, 36 pin DIL male.
- 2 Paddle interfaces, 2 x 6 pin DIN female.
- Stereo audio output, 6 pin DIN female.
- UHF video and audio output, RCA (cinch) female.
- AC power input, with voltage selector 220-110 volt, figure 8 shape AC power 2 pins male.
- System software:
- a machine code monitor with the following commands:
LOOK
DISPLAY
GO
FILL
SUBSTITUTE
MOVE
EXAMINE
EXAMINE REGISTERS
VECTOR EXAMINE
VECTOR EXAMINE BYTES
READ
WRITE
- a built in DAI BASIC interpreter.
- a machine code monitor with the following commands:
- the system was also supported with an 8080-Assembler.
- miscellaneous: a true random number generatorimplemented in hardware.
DAI the company
Data Applications International (DAI) was a company from the end of the 1970s to the early 1980s based at Dreve de Renards 6, Brussels that was specialized in creating "Real World Cards", computer peripheral cards based on their own proprietary DCEbus, which in essence consists of three groups of eight I/O lines (coming from an Intel 8255) . These were Eurocard compatible cards in a 19-inch rack. Most cards were also based on a single Intel 8255 chip. Around 1977 they designed the DAI Personal Computer. On May 6, 1982 the company went bankrupt.[3] The Indata company continued manufacturing DAI computer until 1984.
Video games
There are 6 known commercially released games for DAI PC.[16]
Title | Release year | Publisher |
---|---|---|
Chasse Sous-marine | 198? | Data Applications International |
Daylaxians | 1983 | Dialog Informatique |
De Acrobaten | 198? | Data Applications International |
Jeu de Morpion | 198? | Data Applications International |
Le Chateau des Sortileges | 198? | Data Applications International |
Mensch Ärgere Dich Nicht | 1982 | Sigg, M. |
References
- ^ a b c "DAI INDATA". www.old-computers.com. Retrieved 2023-01-09.
- ^ "Indata DAI". HCM: The Home Computer Museum. Retrieved 2023-01-09.
- ^ a b c Kraan, F.J. (2020). "DAI". Yet another computer museum. Archived from the original on 2022-01-29. Retrieved 2023-01-09.
- ^ "DAI Review" (PDF). Practical Computing: 63. February 1981.
- ^ a b "DAI Personal Computer (1980)". Retrieved 2023-01-09.
- ^ "DAI". 1000 BiT. Retrieved 2023-01-09.
- ^ Electronics. McGraw-Hill Publishing Company. 1979. p. 68.
- ^ a b c d "DAI". HomeComputerMuseum. Retrieved 2023-08-15.
- ^ Eisenbach, Sue (October 1980). "DAI PERSONAL COMPUTER". Personal Computer World. pp. 72–76.
- ^ "DAI PERSONAL COMPUTER". 2022-08-17. Archived from the original on 2022-08-17. Retrieved 2023-01-09.
- ^ a b "DAI origin - Yet another computer museum". 2020-09-24. Archived from the original on 2020-09-24. Retrieved 2023-01-09.
- ISBN 9781447154938. Retrieved 29 April 2020.
- ^ (in Dutch) Teleac chooses DAI
- ^ Mikulic, Tomislav (2015). DAI Personal Computer 1981-1988 Low resolution graphics and animation (PDF).
- ^ "Liens vers la documentation technique du DAI Indata". bruno.vivien.pagesperso-orange.fr. Retrieved 2023-01-09.
- ^ Gaming History