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PicoSYM, a SYM-1 emulator on a Raspberry Pico

Emulation of a Synertek Sym-1 on a Raspberry Pi Pico 1 (W).By andysa on the emulation forum on 6502.orgHere is ...

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KIM-1 Mod. A real KIM-1 in portable format!

KIM-1 Mod. A real KIM-1 in portable format!

Small enough to take with you traveling, battery powered and thanks to the FRAM the contents of RAM are kept ...

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2N5371 pinout

Amazing it works: transistors placed wrong and they still work in the KIM-1

After publishing the photos of the transistors used in the KIM-1 a discussion started on forum64.de in the 'Instandsetzung und ...

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Which transisors are used in the KIM-1?

Which transisors are used in the KIM-1?

Even a microprocessor based computer as the KIM-1 required some simple transistors.To drive the LEDs some extra current is needed, ...

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Last KIM-1 production date: KIM is Dead!!! Long live KIM!!!

Last KIM-1 production date: KIM is Dead!!! Long live KIM!!!

While we may date the first commercial shipping of the KIM-1 to January 1976 (date of the first edition of ...

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50 years of KIM-1: a demo to celebrate

A demo by friend Nilshttps://www.youtube.com/watch?v=aikJvjdEDto&t=208ssource@github: https://github.com/netzherpes/KIM1-Demo

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Why the KIM-1? Jim Butterfield has a good explanation

Jim ButterfieldAug 19, 1999, 9:00:00 AMtoJoe Forster/STA wrote:>> Can you, please, explain me in short what this KIM-1 machine> is: CPU, ...

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50 years of KIM-1 and me

With any product it is not always easy to establish a 'day of birth'.For the 6502 it is the WESCON ...

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10 PRINT for KIM-1 and AIM 65

Michael Doornbos (of https://imapenguin.com/) posted two "10 PRINT" articles for our beloved small 6502 SBC's. The KIM-1 version displays on ...

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Replica of the MTU K‑1002 audio card  and software by Eduardo Casino

Replica of the MTU K‑1002 audio card and software by Eduardo Casino

A faithful replica of the K‑1002 8‑bit audio Digital‑to‑Analog Converter card and software for the KIM‑1, SYM‑1, and AIM‑65 computers, ...

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KIM UNO page updated

KIM UNO page updated

The KIM UNO, the little cheap KIM-1 hardware emulator needed some information added. Photos, links, text.Like the recently acquired KIM ...

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Transform a Commodore 1541 into a KIM-1

By replacing the ROM(s) of a Commodore 1541 disk drive it can be made in a KIM-1.Well, it runs the ...

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RIOT 6530-005 mystery solved!

The MCS6530-005 was known to me only by some lines in MOS pricelist and a remark in an OSI appnote ...

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KIM-1 Simulator can now be used with serial terminals

KIM-1 Simulator can now be used with serial terminals

And now the KIM-1 Simulator can also use a serial terminal, external or a terminal emulator such as Teraterm, Minicon, ...

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Jolt/SuperJolt/TIM Simulator now has serial input/output

The TIM Simulator comes with a 'console', a glass teletype 24x80 screen. It has a subset of ANSI/VT100 support.Jolt/SuperJolt/TIM Simulator ...

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Jolt pages extended

Jolt pages extended

The Jolt by Micro Associates, Inc, is one of the first 6502 systems. A small SBC with a 6502, 6821 ...

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AIM 65 other hardware page added

AIM 65 other hardware page added

For the AIM 65 it was not only Rockwell that produced hardware like video,serial and FDC cards, others also ...

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KIM-1 Marquee

This has been waiting some time to be published.Udo Juerss wrote in 2024 a program KIM-1 Marquee to display running ...

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Jolt replica by Scott LaBombard

Jolt replica by Scott LaBombard

Scott LaBombard started many years ago on a replica of the Jolt. Quite a challenge, since only photos are known. ...

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Alternative Junior Monitor

Alternative Junior Monitor

Udo Juerss minimized the original monitor written by Alois Nachtmann by removing the socalled "assembler". And added Intel Hex and ...

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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.

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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!
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