Home

Latest Posts
I build a RC6502 SBC

I build a RC6502 SBC

I build a RC6502 SBC and a backplane. A kit is available at Hein Pragt's webshop. Nice build, work ...

Read More

Commodore Chessmate

Commodore Chessmate

I have acquired a Commdore Chessmate! Working well.Michael Gardi and Stephen Crane are working on Chessmate emulators. Micheal aims for ...

Read More

Add the Apple 1 monitor to the KIM ROM!

The Apple 1 and the KIM-1 are some of the earliest 6502 systems made.Both are desirable, Apple 1's sell for ...

Read More

Another update to the Simulators

Another update to the Simulators

KIM-1 and TIM Simulator have seen a small update.Improvements on console handling and little annoyances. Focal added as programming language, ...

Read More

Focal-65 V3D for TIM and KIM-1

Focal on the 6502, a page on this small language, originating for Digital Equipment.A small interpreter (about 5K) for a ...

Read More

John Bell Engineering catalogs

Thanks to Dallas Shell I have added the 1984 and 1988 catalog to the John Bell Engineering pages.Also a hand ...

Read More

LJ Learning EMMA update

LJ Learning EMMA update

I have added a page on LJ Technical Learning's Digiac line of 6502 systems.

Read More

End of year updates to my programs

End of year updates to my programs

I have made some small updates to four of my programs. Updates are bugfixes, cosmetic changes to also to let ...

Read More

Tiny Basic by Tom Pittman

Tiny Basic by Tom Pittman

Sources, manuals, articles, patched binaries for KIM-1 and TIM!Tiny Basic for the KIM-1 and the TIM in the SuperjoltTiny Basic ...

Read More

A TIM (6530-004) Superjolt simulator update, also KIM-1 Simulator

A TIM (6530-004) Superjolt simulator update, also KIM-1 Simulator

A TIM (6530-004) Superjolt Demon simulator.Version 0.4. TIM Superjolt Simulator V0.4, Tiny Basic working!Since the TIM Simulator and the KIM-1 ...

Read More

Elektor EC-68 6809

Published in Elektuur/Elektor Computing 3 (Dutch and German) and in issue 100 1986 Elektor France.A 6809 based computer on two ...

Read More

New scans of KIM-1 manuals

I found new high quality scans of KIM-1 manuals on the Retro Commodore website.That website is filled with high quality ...

Read More

Cosmicos donation

Cosmicos is the name for a SBC around the RCA 1802 CPU. Cosmicos stands for COSMAC MINI COMPUTERSYSTEM.Published in the ...

Read More

Superjolt and TIM 6530

Superjolt and TIM 6530

I have acquired 3! Superjolts. With a Synertek Superjolt CP110 manual and Tiny Basic + RAP (assembler) in ROM.A good ...

Read More

V1.3.7 KIM-1 Simulator

New version of the KIM-1 Simulator. Now version 1.3.5. 3 oktober, and now 9 oktober 1.3.7!- text file upload in ...

Read More

Patches to Microsoft Basic K-1008-2L MTU

Patches to Microsoft Basic K-1008-2L MTU

Added to the MTU pages:Patches to Microsoft Basic K-1008-2L sources and binaries, ready to run!

Read More

Micro Technology Unlimited MTU pages enhanced

Micro Technology Unlimited MTU pages enhanced

Dave Plummer (Dave's Garage) received lots of documents on the MTU products with his KIM-1 in a cage system and ...

Read More

New KIM-1 info and more

Added again some KIM-1 information!MDT 650 photos (John Feagans)Scans from the Commodore International Historical Society (Dave McMurtrie):KIM-1 Schematic Poster alternative ...

Read More

MTU K-1008 Visable Memory

All about the MTU K-1008 Visible Memory: documents, programs, images, videos and replica, you find it here.The MTU K-1008 is ...

Read More

KIM-1 Simulator 1.3.0 -> 1.3.4

KIM-1 Simulator 1.3.x adds the improvements from the 1.2.x branch to the V1.1.8 branch. NEw improvements also: bundled with the ...

Read More

This page is about my interest in retro 8-bit small computer systems computing and electronics. And the role of Dutch electronic magazines like Elektuur and Radio Bulletin in the eighties of the 20th century. Also the Dutch users club, called KIM Gebruikersclub, which I joined in 1978 and contributed to as member of the board and as chief editor of the magazine issue 11 to 25.
The retro computing pages are documenting my experiences with 8-bit systems like the KIM-1 and its relatives such as the Apple 1 and the Junior. And various small Z80 and other systems.
I set up this archive as my personal archive of what I research on the subject. If it is of any use for others, fine, enjoy!

Magazines

In the early days of computing, magazines about popular electronics played a big role in making microprocessors available for the beginner, whether the professional or hobby electric engineer. The magazines featured here are the dutch magazines Elektuur and Radio Bulletin. From 1977 until 1996 I worked as technical editor for Radio Bulletin and published about microcomputers and more general electronics.  Elektuur published also articles on these subjects, many are available here.

What is a SBC for me?

A SBC, short for Single Board Computer can be defined as a computer system, based on a microprocessor, on one printed circuit, with keyboard and display, programmable I/O ports, expansion connectors and without a casing. The ‘operating system’ is stored in a (EP)ROM, an often small amount of RAM is available to store programs and data These were the first microprocessor based computers with affordable prices for hobbyists in the late seventies of the previous century. For professionals a way of getting acquainted with the new hardware and learning the basics of programming at a (very!) low level.

IMG_9928
Though it is a complete computer, it has a CPU, memory and I/O, it is also a very limited one. The I/O is often not more than a small keyboard with hexadecimal functions. The display is often not more than 6 or 8 seven segment LED displays, just enough to show, in hexadecimal format, addresses and data. The operating system allows entering and examining of data in memory locations, and start and stop a program. Loading and saving data is limited to either papertape readers and punches, quite common in these days, or via some modulation as data files on audio cassette recorders. Also common is the ability to attach a teletype like the ASR33.

A good example of such a SBC is the KIM-1, shown below. 2K ROM, 1K RAM, many I/O lines free, six LED displays and a keyboard with hexadecimal keys and some function keys.
Why these SBCs like the KIM-1 became so popular? One reason was the low price ($ 280 for a KIM-1, I paid 795 guilders ), so it was in the price range of the average student and hobbyist. Another is the design being open, the complete hardware description and detailed listing of the ROM was included. And it is not the frightening computer, but more a programmable piece of hardware. Because it was so easy accessible and low speed, adding and changing hardware is not hard also. Programming was not easy, but editors/assemblers that could run with some added hardware like RAM and a video terminal made that possible. The nowadays common practice of cross compiling was not available for the hobbyist then.

Besides playing with the SBC, to learn what the microprocessor is capable of, many SBCs were put to work as a sort of PLC, controlling devices in the real world.
What changed the popularity of SBCs was the wish to transfer it to a computer with a better user interface, like graphics on a video screen, a full blown keyboard, a real operating system with mass storage such as floppy drives, and a higher fun factor, a.k.a. games. Or to make it a serious computer fit for business. So SBCs became extinct fast in the mainstream hobby world when the hobbycomputer appeared on the market, like the TRS-80, PET and later the C-64, MSX etc. Even later the boring business PC killed the hobby computer, but that is another story.
It seems the SBC’s are back though: Arduino and Raspberry Pi Contact form to contribute to this fascinating hobby!
IMG_9755