2022 December

AT89C51-8051-8031 SBC

Inspired by an old Elektor (Dutch elektronics magazine) design. I designed a new Eurocard form factor design, with buffered outputs , RAM , EEPROM so that it can also fit the 8051 and 8031’s (ROMless).

NDR School television episodes (26)

0. Microelectronics – Introduction of the NDR “Klein” computerThomas Naumann and Rolf-Dieter Klein introduce the capabilities of the NDR “Klein” computer and the contents of the 26 episodes. (In German).

RetroSys2019 references

NDR Kleincomputer by Rolf-Dieter Klein (For those who speak German) : http://www.ndr-nkc.de/compo/index.htm RC2014 Site : https://rc2014.co.uk/

The Acorn Atom – Introduction

The Acorn Atom was my first “Personal computer”, a computer with a real keyboard, and video display (well actually an old portable B&W TV). All I could effort was the basic version, 2K of Memory, no floating point ROM, no printer interface (6522). For many years my own Acorn Atom ended up in a junk… read more »

Stripping Atoms

As my 2 Acorn Atom boards were in a quite bad state, and I got a hold of a desoldering station that worked pretty well I decided to strip both boards “to the bone”, and rebuild them with high-quality IC-sockets, low profile crystals etc. (Board images are clickable for Hi-Res).

Retrosys2019 Introduction

In 1983 I bought my first book about microprocessors during a summer holiday in Austria, it was titled “Microcomputer selbstgebaut und programmiert” (“Microcomputer self-built and programmed” in English) written by Rolf-Dieter Klein. German television made even a course on it and a lot of the material is still there. Also my thesis was done around… read more »

Welcome to my website

This site has been dedicated to ~1980’s Home- and Game Computers I own, Single Boards Computers (SBC’s) I either built or bought, as well as (Fidelity) chess computers, home-brew hardware and test equipment.

Retrosys2019 Backplane Board

This board was designed in 2018 and also used for some of my other other projects. It has been manufactured , tested (duh, what can go wrong on a plain backplane board). ( Well to be honest, in the first series the mounting holes for the connectors were not 100% aligned but using M2.5 screws… read more »