NEC µPD7220
The NEC µPD7220 or Graphics Display Controller (GDC) 7220 or NEC 7220 for short is a graphics controller.
background
The GDC appeared in 1982 and was developed by NEC . The chip came u. a. used in the NEC PC-9801 , DEC Rainbow 100 and many other computers. The developer was keen to keep production costs low and still get a powerful chip. Production took place in the then modern LSI standard.
Technical specifications
The graphics chip had the following properties:
- DMA skills
- own memory management
- own instruction set (for drawing simple geometric figures such as circles, arcs, rectangles, etc.)
- Up to 256 Kwords (1 word = 16 bit) frame buffer addressable
- Max. Resolution of 2048 × 2048 pixels can be displayed
- bpsw. 1024 × 1024 pixels in 4 color / grayscale plan, i.e. H. 16 colors / grayscale
- Lightpen can be connected directly
Furthermore, several GDCs can be interconnected to e.g. B. to increase the color depth .
Replicas
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In 1987, the construction of the NEC 7220 in the GDR was won through reverse engineering and, due to the political situation, it was subsequently rebuilt as U82720 without licensing the rights holder. It was produced in the VEB Microelectronics "Karl Marx" Erfurt (Combine Microelectronics). It was fully compatible and may not a. in the EC 1834 and the robotron A 5105 educational computer .
Individual evidence
- ↑ http://electrickery.xs4all.nl/comp/qx10/doc/Mc7220_summary.txt
- ↑ http://www.vintagecomputer.net/fjkraan/comp/qx10/doc/nec7220.pdf
- ^ Peter Salomon: The history of the microelectronic semiconductor industry in the GDR . Funkverlag Bernhard Hein eK, 2003, ISBN 3-936124-31-0 , pp. 76-77.
- ↑ www.robotrontechnik.de - The history of computer technology in the GDR. In: www.robotrontechnik.de. Retrieved September 13, 2015 .