Elektor Junior Computer
Encyclopedia
The Elektor Junior Computer was a simple 6502
based microprocessor development board
published in the 1980s in the Dutch, German and later French, Spanish and British versions of Elektor/Elektuur
, in the form of a series of articles, and four books. It was developed by the German engineer Loys Nachtmann.
The Junior Computer was a virtual clone of the KIM-1
, only it did not use the special I/O+ROM chips (MCS6530) but rather an off the shelf 6532 PIA
and a 2708 1K EPROM
. It also had a different physical shape, as it used the Eurocard board, and a 31 pin-DIN connector for I/O and a DIN 41612
connector for system expansion. It was delivered as a electronic kit, or could purchased as two printed circuit board
s (main board and Seven-segment display
board) only, for components to be installed.
As it was much lower in price than an original KIM, many more Junior computers (several thousands) were used in the Netherlands, Germany and France, than original KIM-1s.
Later extension boards were developed, and a BASIC interpreter was ported.
Elektor Expansion boards specifically for the Junior were an I/O Interface card (including a 6532 VIA
, a Tape Recorder interface and a RS232 port), a VDU (video terminal) (an improvement of the previous "elekterminal" design), an EPROM and SRAM
expansion board, an 16/64KB DRAM
board and EPROM programmer
board, and even a floppy disk controller
, as well as a dozen smaller boards for small improvements and interfaces etc.
MOS Technology 6502
The MOS Technology 6502 is an 8-bit microprocessor that was designed by Chuck Peddle and Bill Mensch for MOS Technology in 1975. When it was introduced, it was the least expensive full-featured microprocessor on the market by a considerable margin, costing less than one-sixth the price of...
based microprocessor development board
Microprocessor development board
A microprocessor development board is a printed circuit board containing a microprocessor and the minimal support logic needed for an engineer to become acquainted with the microprocessor on the board, and to learn to program it...
published in the 1980s in the Dutch, German and later French, Spanish and British versions of Elektor/Elektuur
Elektor
Elektor is a monthly magazine about all aspects of electronics, first published as "Elektuur" in the Netherlands in 1960, and now published worldwide in many languages including English, German, Dutch, French, Greek, Spanish, Swedish, Portuguese and Italian with distribution in over 50 countries...
, in the form of a series of articles, and four books. It was developed by the German engineer Loys Nachtmann.
The Junior Computer was a virtual clone of the KIM-1
KIM-1
The KIM-1, short for Keyboard Input Monitor, was a small 6502-based single-board computer developed and produced by MOS Technology, Inc. and launched in 1976...
, only it did not use the special I/O+ROM chips (MCS6530) but rather an off the shelf 6532 PIA
MOS Technology 6532
The 6532 RAM-I/O-Timer was an integrated circuit made by MOS Technology, as well as second sources such as Rockwell. It incorporated 128 bytes of static RAM, two bidirectional 8-bit digital I/O ports, and a programmable timer. This high degree of integration made it quite popular in the late 1970s...
and a 2708 1K EPROM
EPROM
An EPROM , or erasable programmable read only memory, is a type of memory chip that retains its data when its power supply is switched off. In other words, it is non-volatile. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages...
. It also had a different physical shape, as it used the Eurocard board, and a 31 pin-DIN connector for I/O and a DIN 41612
DIN 41612
DIN 41612 is a DIN standard for electrical connectors that are widely used in rack based electrical systems. Standardisation of the connectors is a pre-requisite for open systems, where users expect components from different suppliers to operate together. The mostly widely known use of DIN 41612...
connector for system expansion. It was delivered as a electronic kit, or could purchased as two printed circuit board
Printed circuit board
A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. It is also referred to as printed wiring board or etched wiring...
s (main board and Seven-segment display
Seven-segment display
A seven-segment display , or seven-segment indicator, is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot-matrix displays...
board) only, for components to be installed.
As it was much lower in price than an original KIM, many more Junior computers (several thousands) were used in the Netherlands, Germany and France, than original KIM-1s.
Later extension boards were developed, and a BASIC interpreter was ported.
Elektor Expansion boards specifically for the Junior were an I/O Interface card (including a 6532 VIA
MOS Technology 6532
The 6532 RAM-I/O-Timer was an integrated circuit made by MOS Technology, as well as second sources such as Rockwell. It incorporated 128 bytes of static RAM, two bidirectional 8-bit digital I/O ports, and a programmable timer. This high degree of integration made it quite popular in the late 1970s...
, a Tape Recorder interface and a RS232 port), a VDU (video terminal) (an improvement of the previous "elekterminal" design), an EPROM and SRAM
Static random access memory
Static random-access memory is a type of semiconductor memory where the word static indicates that, unlike dynamic RAM , it does not need to be periodically refreshed, as SRAM uses bistable latching circuitry to store each bit...
expansion board, an 16/64KB DRAM
Dram
Dram or DRAM may refer to:As a unit of measure:* Dram , an imperial unit of mass and volume* Armenian dram, a monetary unit* Dirham, a unit of currency in several Arab nationsOther uses:...
board and EPROM programmer
Programmer (hardware)
In field of computer hardware, the term programmer, chip programmer or device programmer refers to a hardware device that configures programmable non-volatile circuits such as EPROMs, EEPROMs, Flashs, PALs, FPGAs or programmable logic circuits....
board, and even a floppy disk controller
Floppy disk controller
A floppy disk controller is a special-purpose chip and associated disk controller circuitry that directs and controls reading from and writing to a computer's floppy disk drive . This article contains concepts common to FDCs based on the NEC µPD765 and Intel 8072A or 82072A and their descendants,...
, as well as a dozen smaller boards for small improvements and interfaces etc.