Historical Computer Engineering - calculator
Mode: Visitor // Expert
Language: Deutsch English

calculator

  • v. Chr.
  • 1935
  • 1936
  • 1950
  • 1955
  • 1965
  • 1973
  • 1975
  • 1976
  • 1983
  • 1984

Electronical calculator

KC 85 series

General

The KC 85/1 was developed at VEB ROBOTRON Center for Research and Technology developed. Like the first home computer with DDR-called "Z9001", which was developed parallely. Against all rules of "socialist planned economy" the VEB Mikroelektronik Mühlhausen (MPM) developed on the basis of seizure types of DDR-microprocessor system U880 (a replica of the internationally known Z80 system) also a home computer with the name "HC900". Both were introduced in 1984 the Eastern German public. Already at the beginning of 1985 with production launch, it turned out quickly that these products sated the "social demand", ie for industry, education and not to forget - especially on the millitary needs of calculators

KC 85/1

KC 85/1

The KC85 / 1 is an 8-bit computer with the U880D processor. He had a fixed 16k RAM and 4K ROM. There was no full graphically display avaivable, therefore some extra coded graphical signs beneeth the Basic-Code were used for displaying. The resolution was 40x20 or 25 characters per line. The keyboard was built into one the calculators case and had very small elastomer keys, which bring problems by ​typing long programs. The BASIC interpreter was not ROBOTRON own development, but based on an adapted version of the K1520-BASIC interpreter of the agricultural institute Dummersdorf. The program was available on cassette and had to be recorded by tape directly after starting the computer. Later there was also a module with the BASIC interpreter in ROM. Model for the operating system of the Z9001 was the widespread CP/M-80. The general structure and the external interfaces have been largely taken over. But there are differences in commands and the resident working with external data sources. These commands were replaced by Z9001-specific files and the work was adapted to the possibilities of the computer (just cartridge as an external disk). A further development of the Z9001 (KC85/1) was the KC87.

Processor U880D (Z80) / 2,4576 MHz
Working memory 17 KByte with usable 16 KByte
Read-only memory 6 KByte ROM
Memory extention max. 64 KByte with modules
Display 24 lines x 40 symbols (20 lines x 40 symbols)
Symbolic graphics 128 graphical symbols
Color 128 graphical symbols
Keyboard alphanumeric keyboard with 65 keys
externernal memory Magnet cassette drive
external interfaces TV, Tape, I/O, 2 levers, 4 modules for extentions
Sound Buzzer
Programming languages BASIC, Assembly
Chasis Compact computer with integrated keyboard
Weight 4,1 kg
Price KC85/1 1500,- GDR-Mark (1986)
KC87.30 960,- GDR-Mark (1989)
KC87.31 1300,- GDR-Mark (1989)
Manufacturer VEB Robotron-Meßelektronik "Otto Schön" Dresden