My 6502 systems

I have added a page with photos of my 6502 systems. From the KIM-1 to the A-One extended and Micro KIM to the Pocketerm. Includes Junior and Elektuur bus systems like EC65/Octopus.

IMG_9772 IMG_9755 IMG_9787 IMG_9779

6530 6532 TIM 6530-004


The KIM-1 has two 6530 IC’s, the 002 and 003. From some research I have found that this factory mask rommable I/O RRIOT has been produced in more versions.

An interesting one is a relative of the KIM, the Terminal Interface Monitor 6530-004. Meant for a minimal 6502 development system, it contains a teletype oriented monitor program and a serial interface via bit banging.
See the TIM 6530-004 page for more information.

But there were more 6530’s produced (and the list must be incomplete since lots of sequence numbers are missing. like 001.

6530-002 KIM-1 listing in KIM-1 Users manual
6530-003 KIM-1 listing in KIM-1 Users manual
6530-004 TIM Terminal Monitor, see the TIM page
6530-005 According this OSI appnote this is an unprogrammed version of the 6530. I have seen ads for this part without description of what this is.

6530-009 Allied Leisure pinball (IC5)
6530-010 Allied Leisure pinball (IC6)
6530-011 Allied Leisure / Fascination pinball (IC3)
6530-013 ?

6530-024 Commodore CHESSmate (based upon Peter Jennings MicroChess)

Commodore diskdrives

901466-01 6530-??? DOS 1.0 Shugart SA390 2040, 3040 and 4040
901466-02 6530-028 DOS 1.2 Shugart SA390 2040, 3040 and 4040
901466-04 6530-034 DOS 2.0 DOS 2.1 Shugart SA390
901483-02 6530-036 DOS 2.5
901483-03 6530-038 DOS 2.5 Micropolis 1006-II (8050)
901483-04 6530-039 DOS 2.5 Tandon TM100-3M (8050)
901884-01 6530-040 DOS 2.7 Tandon TM100-3M (8050) Tandon TM100-4M (8250)
901885-01 6530-044 DOS 2.7 Micropolis ???
901885-04 6530-047 DOS 2.7 Micropolis 1006-II (8050) Micropolis 1006-IV (8250) Micropolis 1106-II (Safari, mit Garagentor, 8050) Micropolis 1106-IV (Safari, mit Garagentor, 8250)
901869-01 6530-048 DOS 2.7 M.P.I. 101SM (8050)M.P.I. 102?? (8250)
251256-02 6530-050 DOS 2.7 Matsushita JU-570-2 (8250LP)
251257-02A 2716 DOS 2.7 Matsushita JU-570 (SFD-1001) Matsushita JU-570-2 (SFD-1001)
251474-01B 2716 DOS 2.7 Matsushita JU-570-2 (8250LP)


TIM 6530-004

Terminal Interface Monitor, short TIM, with codename 6530-004, is a 6530 with a monitor program in the mask ROM. No systems were sold by MOS around it, just a kit with manual and the IC.
The Jolt did use a TIM IC, see the Jolt and Super Jolt page.
The DATAC 1000, a single-board computer based upon a 6502 and a TIM RRIOT, designed in 1976 by Philadelphia Area Computer Society club members Carmen DiCamillo and Roland James.

Information on this page:
The story of the TIM
Functions of the TIM software in ROM
TIM MANUAL JUNE 1976, 1977 Rockwell
TIM bytes the Apple
3 articles from Micro journal on the TIM
Article on how to expand TIM
TIM and OSI 400
Breakpoint routine for 6502s TIM
Lunar Lander for TIM and Jolt
A Christmas story about a Tiny TIM, by Joseph Watson
TIM-2, a recreation of a TIM system with a 6532, Peter Renaud

The story of the TIM (from Ch.1.5 of  “On the Edge: the Spectacular Rise and Fall of Commodore”)

The first development system offered by MOS, the TIM IC, was in kit form, which reduced the selling price to only $30. Since the unit was designed primarily to instruct the user on the workings of computer systems in general and the 6502 in particular, MOS Technology contracted Microcomputer Associates of Santa Clara, California to write the unit’s internal program. The two founders, Ray Holt and Manny Lemas, taught engineers how to use microprocessors. Peddle relates, “You have to understand how little the world knew of microprocessors in 1974, ‘75 and ‘76. There were guys making big money selling classes on microprocessors during that time.” Manny Lemas had worked for Peddle during his GE days, while Ray Holt had an impressive background working on the F-14 Tomcat project for the Navy.

In the middle Manny Lemas, on the right Ray Holt

The technicians developed the system in a special research area on the second floor of MOS Technology. The lab was a room within a room, with a large sign on the door in capital letters warning NO ADMITANCE. Inside, the team stared intently at oscilloscopes or sat over hot irons soldering components onto circuit boards. Small pieces of circuitry were scattered chaotically across the room. Since the 6502 microprocessor and supporting chipset contained almost everything necessary for a computer, the design was minimal. When assembled, it could be connected to a teletype machine or a computer terminal.

The biggest job was programming the built-in ROM code for the computer. This consisted of a debugger and monitor program, appropriately called the Demon. According to Peddle, Demon was programmed by Manny Lemas and Mike Quarter, who previously developed Peddle’s time-sharing system. The programmers used this time-sharing system to develop the code, which they burned into a 6530-004 RRIOT chip. This little powerhouse included RAM, ROM , I/O and timer capabilities.

The system was named simply. Peddle and his team liked acronyms, thus the Terminal Interface Monitor, or TIM was christened. TIM would begin a predilection at MOS Technology and Commodore for assigning friendly three-letter names to their products.
Those ordering the $30 development kit received the grey-ceramic 6530-004 chip and a manual consisting of 14 sheets of 11×17 paper, folded and stapled in the middle. Included in the manual were a suggested schematic, the TIM monitor commands, a few sample programs and a listing of the monitor code. It was up to the user to provide the resistors, transistors, capacitors, wire, and even the 6502 microprocessor.
Though receiving a computer in the form of a kit does not seem particularly user friendly now, hobbyists at the time clamored to build their own computer. Nonetheless, a good portion of the kits failed to operate upon completion. Rather than using a prepared circuit board, many buyers simply wire-wrapped the chips together on a piece of generic perf board or prototyping board, often termed a kludge board. After placing the required components on the board, builders hand wired the chips one pin at a time, resulting in a snarl of fine multicolored wires. Once the chips were in place, the user then had to construct or purchase a separate power supply for the TIM. Finally, the TIM was (as the name suggests) able to interface with a standard ASCII terminal or teletype machine.
As hoped, the do-it-yourself nature of the kits spawned familiarity with the products, and once hobbyists had invested time learning about the chip, they often remained loyal to the 6502. Many hobbyists ended up using their TIM computer as a small development system, since it was ideal for creating small programs. For their part, MOS Technology continued to sell TIM computer kits to diehard hackers, even after the Commodore acquisition. Ultimately, TIM was just a stepping-stone to developing and marketing a fully assembled computer.

Functions of the TIM software in ROM

• Self adapting to any terminal speed from 10-30 cps,
• Display and Alter CPU registers,
• Display and Alter Memory locations,
• Read and Write/Punch hexadecimal formatted data,
• Write/Punch BNPF format data for PROM programmers,
• Unlimited breakpoint capability,
• Separate non-maskable interrupt entry and identification,
• External device interrupts directable to any user location or defaulted to DEMON recognition,
• Capability to begin or resume execution at any location in memory,
• Completely protected, resident in Read Only Memory,
• Capability to bypass DEMON entirely to permit full user program
control over system,
• High speed 8-bit parallel input option, and
• User callable I/O subroutines.
DEMON’s Command Set Includes:
.R Display registers (PC,F,A,X,Y,SP)
.M ADDR Display memory (8 bytes beginning at ADDR)
: DATA Alters previously displayed item
.LH Load hexadecimal tape (socalled MOS papertape format)
.WB ADDR1 ADDR2 Write BNPF tape (from ADDR1 to ADDR2) (Intel papertape format)
.WH ADDR1 ADDR2 Write hexadecimal tape (from ADDR1 to ADDR2)
.G Go, continue execution from current PC address
.H Toggles high-speed-reader option (if it is on, turns it off; if off, turns on)

I know of two commercial systems using the TIM:
The Jolt and Superjolt, Microcomputer Associates/Synertek (also information on the origin of the TIM-1 program!)
– the first Brutech BEM bus system, A small dutch company, Vinkeveen, that produced professional 6502/6809 and more, industrial systems.

Frank Wolf has decapped a TIM 6530-004 to study it and maybe do a FPGA clone.

Here the photo’s:

TIM- 1 Manual

PDF TIM manual
DEMON was the name Microcomputer Associates gave to the TIM Monitor. in part 3 another listing of the TIM monitor is given,
DEMON software manual part 1
DEMON software manual part 2
DEMON software manual part 3
KIM-1 User manual in HTML format

And here the machine readable and ready to assemble source, listing and binary  of TIM (Thanks Martin Hoffmann-Vetter)

Expand your TIM


(Design by Fred Hatfield, scans and transcription by Tom Owad,

For those of you that would like to have hard copy capability and much better control over program development on the Apple 1, the following hardware addition will accomplish it.
Using a 6530-004 (‘TIM’ chip) costing about $12.00 gives many superb features such as a variable baud rate serial input/output, a high speed parallel input (high speed paper tape reader), an excellent breakpoint processor, paper tape dump and load routines, etc.
The TTY port is located at locations 6202H and 6203H. Date at that port should be 00H and 16H respectively. The baud rate is stored at 00EAH and 00EBH and 110 baud is represented by 10H and 46H at those locations. It’s a fun addition to the Apple 1. Try it!
Fred Hatfield K8VDU

Teletype connection schematic.

Teletype Pinouts (connections 6530-004 and Apple bus):

      TIM                 APPLE 
     6530-004             6502
        33        D0        33
        32        |         32
        31        |         31
        30        |         30
        29        |         29
        28        |         28
        27        \/        27
        26        D7        26
         5        A9        18
         6        |         17
         7        |         16
         8        |         15
        10        |         14
        11        |         13
        12        |         12
        13        |         11
        14        |         10
        15        AO         9
        16        RES       40
        17        IRQ        4
        1       - GND
       20 - +5V              -----------------------
        3 / PIN25           |  FRED HATFIELD K8VDU  |
          \ 6820            |                       |
       18 - +5V             |     7/77              |

TIM articles in the Micro journal in pdf format:
– Micro 1: Terminal Interface monitor (TIM), introduction and description, with am alternative system circuit diagram.
– Micro 3: TIM meets the S100 bus.
– Micro 9: Two short TIM programs. First a program to chage the baudrate, the second is a small operating system.

TIM and OSI 400

Application note by OSI how to add a TIM to an OSI 400 board.

Breakpoint routine for 6502s

Lunar Lander for TIM



Information on this page:
Datasheets 653x
Known 6530 variants
6530 replacement for Commodore drives
6530 replacement in the KIM-1 clone and Micro-KIM
6530 replacement 6530 in KIM-1
Commodore Chessmate, Novag II, TEC6530 replacement in the Gottlieb soundsystems, the MIOT
Read out a 6530-009 with a KIM-1 clone

The 6530, nick named RRIOT is quite a special IC in the 65xx family.
Timer, RAM (64 byte), ROM, I/O, Counter in one IC. It has a factory mask programmed ROM and the locations of its I/O and RAM and ROM are determined also in the factory.
The 6530 is found in among others the KIM-1 (6530 02, 6530 03), a Chess system with MicroChess by Peter Jennings (6530 24) and variants are used in Commodore disk drives.

The 6532 has no ROM and RAM size is 128 byte versus 64 in 6530. I/O and timer are functional identical to the 6530. The nickname is RIOT, and it is a general purpose I/O device in the 6502 family. Very popular in e.g. the Atari 2600, and many clone KIM-1’s.

There is a datasheet for an IC called the 6531, RRIOC for RAM ROM I/O Counter. I have never seen it in the wild though, but seen references to pinball machines using it.

6530 002 0278
6530 011 7925
6530 003 0680
6530 002 0880
r6530 005p small

A mistery 6530, 021 unknown sofar.


The 6530 was produced by most 6502 manufactures, from MOS Technology/Commodore SG to Rockwell and Synertek. All production datasheets that I have seen afaik identical, here I present some clean Rockwell datasheets. The first one is a preliminary MOS datasheet for the MCS6530, missing the ordering pages of the production version.
MOS Technology preliminary MCS6530
Rockwell 6530 RRIOT
6531 RRIOC
6532 RIOT
How to avoid timer interrupts during reset of the 6502

6530 Rockwell
6531 RRIOC
6532 RIOT

A CMOS version, the 65C32 exists, here a page from the 1983 Synertek Databook.

Known 6530 variants

6530-002 KIM-1 listing in KIM-1 Users manual
6530-003 KIM-1 listing in KIM-1 Users manual
6530-004 TIM Terminal Monitor, see the TIM page
6530-005 According this OSI appnote this is an unprogrammed version of the 6530 TIM. I have also seen ads for this part without further description of what this is.
It has the 16 I/O lines, 64 word RAM and the timer, which can generate an IRQ. One can assume the ROM is empty.

6530-006 Allied Leisure pinball version 1 (IC6)
6530-007 Allied Leisure pinball version 1 (IC3)
6530-008 Allied Leisure pinball version 1 (IC5)
6530-009 Allied Leisure pinball (IC5)
6530-010 Allied Leisure pinball (IC6)
6530-011 Allied Leisure / Fascination pinball (IC3)

6530-013 Used in the CBM 2040/3040/4040 disk drive DOS 1.0
6530-014 used in the Gottlieb System 1 sound boards
6530-016 Used in Gottlieb system 80/80A/80B sound boards

6530-024 Commodore Chessmate (based upon Peter Jennings MicroChess)

6530-241 MIOT in pinball machines
6530-243 MIOT in pinball machines

Commodore diskdrives

901466-01 6530-??? DOS 1.0 Shugart SA390 2040, 3040 and 4040
901466-02 6530-028 DOS 1.2 Shugart SA390 2040, 3040 and 4040
901466-04 6530-034 DOS 2.0 DOS 2.1 Shugart SA390
901483-02 6530-036 DOS 2.5
901483-03 6530-038 DOS 2.5 Micropolis 1006-II (8050)
901483-04 6530-039 DOS 2.5 Tandon TM100-3M (8050)
901884-01 6530-040 DOS 2.7 Tandon TM100-3M (8050) Tandon TM100-4M (8250)
901885-01 6530-044 DOS 2.7 Micropolis ???
901885-04 6530-047 DOS 2.7 Micropolis 1006-II (8050) Micropolis 1006-IV (8250) Micropolis 1106-II (Safari, mit Garagentor, 8050) Micropolis 1106-IV (Safari, mit Garagentor, 8250)
901869-01 6530-048 DOS 2.7 M.P.I. 101SM (8050)M.P.I. 102?? (8250)
251256-02 6530-050 DOS 2.7 Matsushita JU-570-2 (8250LP)
251257-02A 2716 DOS 2.7 Matsushita JU-570 (SFD-1001) Matsushita JU-570-2 (SFD-1001)
251474-01B 2716 DOS 2.7 Matsushita JU-570-2 (8250LP)

Via an adapter board Commodore reused older 6530’s with new firmware by disabling the built in ROM and adding a 2716.
See Zimmers Commodore archive. Note that not just any 6530 can be used in this way, only the 6530’s from the Commodore diskdrives. A more general approach with a 6532 is described below.

A similar hack is replacing a non-functional KIM 6530 with a 6532, a 2716 and some glue logic: Gilbert Coville) and


The Micro-KIM, see the whole story here,  is another variant of a KIM-1 with the original ROMS and 6532 instead of 6530.

See the complete circuit (version 2009!) here.

Use a KIM-1 (clone) to read out a 6530-009

TODO: add 6530-009 rom bin and assembly


The DOS65 system, designed by the KIM Gebruikers Club, based upon an Elektuur Octopus design, augmented with a better floppy controller is now documented on the DOS65 page.



VAE T4 system

The dutch company Visser Assembling Electronics, Alkmaar, working for and in cooperation with the dutch carpet-factory Forbo Krommenie, developed a system based upon the KIM-1.
The T4 system consist of a large portfiolio of RAM, ROM, EPROM, input (Analog and Digital) and Output boards. Also a videoram card was developed.

Scanned documentation and all photos of the system





MCS Alpha 1

MCS Alpha 1

The ALPHA-1, made by Berliner Unternehmens MCS (“Micronic Computer Systeme GmbH”) is an early computer, produced in 1977. The design is influenced heavily by the KIM-1 with many improvements and enhancements.

It is ready to run, has a KIM-1 compatible cassette file format. The system exist of an external CPU board and a  cased display/keyboard I/O system.

mcs alpha 1

Documents in PDF format:

Article in Radio Bulletin, August 1979, written by me
User guide Band 1 and Band 2 (scanned by me)
Alpha Handbuch Okt 1977 (different scan, missing 6532 appendix
Mona 2 listing
Mona 2 in hex format
Von Alpha bis Omega MCS Alpha 65, CHIP 1978

Other MCS products around the MCS-bus

MCS Basic V2.0
M622 CPU card
M628 I/O card
M628 sockets
M639 Floppy interface
M677 Floppy interface
FDOS V2.0 Floppy disk system
M660 SBC 6502 card with MONA 4 ROM listing
M6660 Connectors
Mona 4 in hex format
DRDIS V4 in hex format
Loader V41 in hex format
M687 A/D converter
M688 D/A converter
M707 32 K DRAM
M764 6522 I/O card

mcs alpha 1

mcs alpha 1

mcs alpha 1

mcs alpha 1

mcs alpha 1

Apple 1 replica’s

About the Apple 1, and modern clones I have like the A-ONE and the Replica 1.

All of us older computer geeks know that before selling Macs, Apple founders Steve Wozniak (the genius) and Steve Jobs (the greedy business man) had a lot of success with the Apple ][ or Apple 2 or Apple ii, whatever marketing tricks were done with the name of that remarkable personal computer. The 2 in the name suggest there was an Apple 1 and yes, there were a very limited numbers of boards sold (200 or so, 50 or so survived time, so its a valuable collectible) branded Apple 1 in the 1976-77 time-frame. It has video on board and accepts input from a full size keyboard, so it is one of the first standalone hobby/personal computers based on a microprocessor, the 6502 of course, being powerful and cheap at that moment.

What is an Apple 1?

Besides being the first product of Apple Computers and designed by Steve Wozniak, the Apple 1 featured as one of the first a complete computer, with keyboard and video, on one board, based on an affordable and powerful microprocessor, the 6502.

Apple 1 replica

Apple 1 Replica

There are several Apple 1 clones made! The Replica-1 SE by Vince Briel was the first to apply modern components to replace the hard to get and therefore expensive components, like the Signetics 2513 and such, with modern microprocessors emulating the terminal part. The terminal part is replaced by three microcontrollers, for video and serial interface. Before he made the Micro-KIM, Vince Briel designed quite a complex replica of the Apple 1. Complex because of the now defunct, hard to get components. He worked around that problem beautifully with innovative modern solutions and added conventient modern connections like USB and PS/2 keyboard. The result is the Apple 1 Replica (SE). Available are a slot expansion for three real Apple 1 slots, a multi-I/O board with ACIA 6551 and 6522 VIA and, via Rich Dreher, the CFFAA1 (Compactflash mass memory) board.

Here a collection of pages on Replica 1 designs.

Of these Replica’s I have in my collection the Replica 1 SE and the A-ONE extended. Both excellent computers wit some differences:

  • The A-ONE is even more compact, less IC’s.
  • The A-ONE has a real Apple 1 slot instead of the pin header on the Replica-1 but in shrinken format!
  • No parallel keyboard interface on the A-ONE, the PS/2 input functions as the keyboard. On the Replica both parallel and PS/2 can be used.
  • Selection of NTSC or PAL on the A-ONE delivers a rock solid picture.
  • The Replica-1 has USB, also functioning as power supply, as an option also as serial interface.
  • The Replica-1 has an AT(X) power connector, required for the -12V of the parallel Apple keyboard.
  • The Replica 1 has a EEPROM, the A-ONE an oldfashioned EPROM.
  • The forum of Briel Computers for the Replica-1 gives good support for the community.
  • The Replica 1 is still available for sale as Plus
  • The CFFA1 card delivers mass storage to the Apple 1 but the A-ONE is connector is not the right size.

Apple 1 specifications

(Specifications from from the original manual)

In fact the Apple 1 is made up of:

  • A 6502 based microprocessor system with 4K RAM (dynamic ICs) and 256 bytes ROM
  • A ‘monitor’ program called WOZmon (written by Steve Wozniak, in those 256 bytes!)
  • A video terminal, made with dynamic shift registers, a uppercase only character generator (the famous Signetics 2513)
  • Connector for parallel ASCII keyboard

The microprocessor and he terminal part are glued together via a PIA 6821. One 8 bit parallel port reads the ASCII keyboard, the other port delivers the characters to be displayed on the video terminal.

Apple 1

APPLE I_Operation Manual
Apple 1 Basic Manual
Apple 1 Cassette Interface manual
Redrawn Apple 1 circuit diagram
Truetype Apple 1 (2513 IC) font


An archive with my collection of Apple 1 software, hex files, bin files, sources, extended monitor, games, utilities, assembler. See also the Replica 1 and A-ONE pages for more software.

Datasheets of the now rare Signetics ICs in the Apple 1 (available on every Apple 1 page, but they are all the same documents scanned by me, Hans Otten!)

Apple 1 monitor
The Apple 1 comes with the WOZ monitor. A very small but smart program, since there is only 256 byte available in the PROM of the original.

It can do just the basic:

1. The prompt is  ‘@’
2. Enter one or two hex numbers, separated by a dot, and it shows you the content of memory from first to last number
3. Enter a hex number to be put in memory, by specifying the address, a ‘:’ and then the hex number for that memory location. Or as many bytes for consecutive locations.
4. Run a program from a memory location.

The monitor is so simple, smart enough to be usable for the replica’s. Via the serial interface you can dump standard hex files to the Apple 1!

The API of the Apple 1 is not much more than:

1. read a character from the keyboard
2. Read a line form the keyboard
3. Write a character on screen
4. Write a hex string to the screen

When the optional cassette interface is added, some more command are added to read and write data from and to an audio cassette tape recorder. Be warned, the Apple 1 cassette interface is very strict about the quality of the tape and the qualiy of the power supply! With other words, its a disaster to work with.

Apple 1 Basic

Steve Wozniak wrote, by hand, no assembler used, a Basic interpreter for the Apple 1, fitting in 4K. No floating point, a pre-runner of Integer Basic for the Apple 1.
Good enough to run simple Basic programs, 4K is not much memory. Mostly text based games. Some are still available.

Krusader and A1 Assembler

Ken Wessen has produced an assembler, disassembler and debugger and even added a small powerful machine monitor . The program is called Krusader and it fits in 4K. Built in in the Apple 1 Replica and the A-ONE.

Visit the Replica 1 software page where also a working version of the Apple 1 emulator POM-1 can be found.

San Bergmans produced also an assembler package for the Apple 1, called A1 Assembler. A small sister or subset of his impressive SB-Assember. More powerful than the Krusader assembler, but no debugger. Can be used on any Apple 1 replica and is built in in the A-ONE.

You can find a large collection of Apple 1 software in the githib archive of Jeff Trantor.

Programming languages

Ports of Lee Davison’s excellent 6502 Basic, and Figforth are available. For these you will need the A-ONE or Replica since these have 32K RAM to play with.

Cross assembling/compiling

Any 6502 assembler on another platform that can produce hex files can be used to develop programs on the Apple 1. Dont worry about the Apple 1 API, since there is nearly nothing …

The CC65 package, a C compiler and assembler for the 6502, can also be used with the Apple 1 CC65 patches


Elektor Elektuur Junior

Elektuur/Elektor and the Junior Computer and other 6502 based machines.

The Junior computer design was published by Elektuur/Elektor from 1980 on. It was published in a series of magazine articles, four books and several socalled paperware A4 booklets. Loys Nachtmann designed and developed the the Junior Computer. G.H. Nachbar did the Dutch translation of the German books. The 4 Junior books were translated into English, German, Spanish, Italian and French as well.

The Junior design is in fact heavily inspired by the hardware of the KIM-1 (or call it a clone ..), the floppy interface design is based on the Ohio Scientific OS65D design. It was delivered as a kit or could be be built from only the PCB’s sold by Elektuur. Many hobbyist have build one. Later extended with an adapted version of the 8K KB9 Basic and even a disk operating system (Ohio Scientific DOS OS65D).
Articles in the Elektuur magazine and books (1-4), a 6522 book in the same series, in Dutch, English, French and German have been published.

Quickly adopted by the Dutch KIM Gebruikers Club because it was so close to the KIM-1. In the later days the number of Junior Computer users exceeded the KIM-1 users and changed the nature of the club from professional users to a hobby club. It also led to the DOS65 operating system for the Elektuur 6502 CPU board

The magazine Elektuur (the Dutch name) and Elektor (the name in many European countries) surprised us in 1980 with the publication of a build-yourself 6502-based SBC. It is a design in the tradition of the KIM-1 and SYM-1: a hexadecimal keyboard, six hexadecimal led displays and KIM-1 compatible tape format.
Many Junior Computers were built, either from the PCB made by Elektuur and separate components or as a complete kit. And after we (Anton Muller and me) sent a letter to the Elektuur magazine that got published about the KIM Gebruikers Club, many hundreds Junior users joined the club.
The developments after the Junior design in Elektuur led to the EC65(K) (see the Elektor Computing books) and the KIM Club DOS65, documented on this page.

What you can find here:


EMUF stands for Einplatinen-Mikrocomputer für Universelle Festprogrammierung.

First published in the german magazine MC Die Mikrocomputer-zeitschrift nr 2 1981, and later published in a special called ‘Das EMUF sonderheft’. Also a book was written called ‘Mit Computern steuern’.


In this magazine and books a tiny 6504 CPU based system is described, consisting of a minimal 602 system with a 6504, a 6532 and an EPROM

In 1984 an update to the EMUF-6502 was published, a second 6532 to double the I/O

Around this system a number of practical I/O circuits and programs are described.

Scanned magazine articles 1981 1986, contents see below

Scanned EMUF-Sonderheft

Thanks to Dick Blok for the scan of the Sonderheft.

Das EMUF-Sonderheft 2

Scanned Das EMUF Sonderheft 2

Thanks to Mathias Ohlerich for the scan of the Sonderheft 2

Contents of Scans from the MC magazine 1981 – 1986 (incomplete, see the MC page)

MC Die Mikrocomputer-Zeitschrift
Juli/August 1981
Madchen fur alles
EMUF Programmiertips
So entsteht eine EMUF-Applikation
1981 3
EMUF bringt Strichcode zum IEC-Bus
1981 4
V24 Interface
1982 6
Kompatible EMUF-Erweiterung
1982 10
EMUF als Schaltuhr, Thermometer und Frequenzmesser
1982 11
Erweiterter EMUF
1983 1
IEC-Centronics Interface
1983 3
EMUF lernt sprechen
1983 4
EMUF in Senegal
1985 3
Der Eier-EMUF
1983 11
EMUF als Morse-Tutor
1984 1
EMUF mal Zwei
CBM und EMUF in der Ausbildung
1984 6
Der Pillen-EMUF
1986 2
EMUF als Bordcomputer
Centronics Interface
1986 6
Es musizieren die EMUFs – CP/M dirigiert

Mit Computern Steuern
Download here