Recent content in Welcome to e‑basteln.de! on e-basteln
One of the things that piqued my interest in the RPC-4000 was the role it plays in the “Story of Mel”. A famous piece of hacker folklore describing the early days of programming – when “abstraction” and “modularity” were not a thing yet. To the contrary, programmers aimed to make full use of all intricacies of a machine to optimize their programs. Any side…
Several builders have designed handy accessories for the paper tape reader. Using mostly 3D-printed parts, they make tape handling more convenient. This page shows photos and provides the CAD files for download. Many thanks to Lars, Nicolas, Walt and Tony for sharing their designs and photos! External tape guides Lars Wind has designed two external paper tape guides which let you switch quickly…
The Pilot ACE computer was built at the National Physical Laboratory in England from 1946 to 1951, based on a design by Alan Turing. While intended merely as a testbed for a full-scale “Automatic Computing Engine”, it was one of the fastest computers of its time, running at a bit clock rate of 1 MHz. Turing came up with a minimalist computer design, a bit-serial architecture which…
This little manual paper tape reader is easy to build and operate. It connects to any modern computer via USB, and performs well with all kinds of 5 to 8 bit paper tape, including translucent paper materials. To compensate for sensor tolerances and adjust to different paper types, it can automatically calibrate its optical sensors. The paper tape reader is controlled by an Arduino Pro Micro.…
This wristwatch displays the time on an original 1970s LED “bubble display”, as used in the early pocket calculators, and sports a beautifully prototypish breadboard look. This is not my own design – the idea, circuit design, and firmware are by Inge P. from Norway. Inge has made a project description and his firmware source code and usage instructions available. Many thanks for…
To use the paper tape reader, simply connect it to a Windows 10, Linux or Mac OS computer via USB. The reader should automatically register as a USB CDC device (communication device class, a virtual serial port). Start a terminal program of your choice and select the right (virtual) serial port. No need to set the baud rate etc., since no physical serial port is involved. The reader will start…
I don’t have step-by-step illustrated building instructions here. But with the sectional view of the PCB stack below and the following hints the build should be straightforward. Sectional view of the stack of PCBs which make the chassis, as well as the key electronic components. For clarity, only 5 of the 8 data sensors and LEDs are shown. × Builder’s hints Preparing the PCBs The…
The 6502 was the CPU in my first computer (an Apple II plus), as well as many other popular home computers of the late 1970s and 80s. It lived on well into the 1990s in game consoles and chess computers, mostly in its updated “65C02” CMOS version. Here’s a re-implementation of the 65C02 in an FPGA, in a pin-compatible format that lets you upgrade those old computers and games to…
The general idea of the 65F02 is straightforward: Load all ROM content from the host computer into on-chip RAM upon startup, then execute everything from on-chip RAM at 100 MHz – except for memory-mapped I/O access, which goes to the external host bus at the original slow speed. But there are a few twists which the 65F02 needs to be aware of. Here’s what I have implemented (but not…
This page hosts my design files and some preliminary documentation, links and acknowledgements for the open source components I use in the design, as well as some links to 65C02 and chess computer resources. 65F02 user information User instructions (English) and User instructions (German) in PDF format. TinyProg programming software, a Python program to re-program the 65F02 FPGA with a new logic…
The Enigma touch is an electronic functional model of the Enigma cipher machine. Various civilian and military variants of the Enigma from the 1930s and 40s can be simulated. A simple single-board design aims to closely replicate the appearance and function. Electronic components are fitted on the bottom side of the circuit board; the top side remains free and is modeled after the front of the…
Collect ‘em all! Released in 1963, the LGP-21 was the last member of Librascope’s family of serial memory computers: Lower cost, a simplified user interface, and slower than the LGP-30. Designing an FPGA replica is meant to be a “practice run” for me – next, I hope to contribute to the restoration of two real LGP-21s at the technikum29 computer museum! A low-cost…
Yes, this feels like a bit of a rehash of my LGP-30 and RPC-4000 replicas… The three computers were quite similar in their architecture, and so are the replicas: Another FPGA replica – collect ‘em all! Like its predecessors, the LGP-21 replica is based on the low-cost Numato Mimas (Xilinx Spartan 6) FPGA development board. A custom front-end board provides all necessary user…
Here’s a preview of how the Enigma touch is used. Please see the Quick Reference card and the User Manual for more details. Routine Operation Basic operation of the Enigma touch is as close as possible to the real machine. When you turn it on, the Enigma touch remembers its most recent machine settings and is ready to encrypt right away: Set your rotor starting positions and start typing and…
Documents in English Reference Manual – a great introduction to the instruction set and user interface, plus reference information on character set, representation of numbers, and optimum placement of data and instructions on the disk. Programming Manual – more details on the instruction set, an introduction to programming, details on number and character representation and tape…
This page hosts documentation and firmware for the Enigma touch, gives sources for suitable rechargeable batteries, and provides external links to information on the original Enigma which I found particularly useful. User information Current version These files apply to the current board revision 5, available via CEDS. Quick reference card in English, A4 paper format. Also available in letter…
The construction of the Verticade cabinet is quite similar to my Asteroids cabinet. Both use a structural frame made of plywood, and front elements – including the control panel – made of Perspex. Frame The cabinet’s structural frame is made from two side panels (9 mm plywood) which are connected by multiple transverse panels: Top and bottom of the marquee box, and internal…
This page is somewhat preliminary. I hope to make it a bit more coherent, add more detail and a few files for download soon! Software setup The software stack which worked well for me comprises: DietPi operating system image, MAME4ALL-Pi emulator, AttractMode front end, RetroGame GPIO driver to connect the joystick and buttons directly to the Raspberry Pi. While I have provided links to the home…
This site describes my ongoing efforts to home-build a Scanning Tunneling Microscope (STM). You may take it as an illustration of the strange things people do with their spare time; but I also hope to encounter a few readers who will consider to embark on that kind of project themselves – or have even done so already, and want to help improve this site by contributing their own experiences.…
This website is built with Hugo. Thanks to the Hugo team for a nice, fast, and free tool to build static websites! The theme is based on Hyde, but with a fair bit of tweaking. What is Hugo? Hugo is a generator for static websites. You run Hugo locally on your development computer, either as a background server or via an explicit command. Hugo processes your description of your web pages, and…
This web site is maintained by Jürgen Müller, Hamburg, Germany. Please contact me via email with any comments or concerns — juergen@e-basteln.de. These pages describe personal hobby projects. They do not pursue commercial interests and are not affiliated with any commercial enterprise. I do not offer any components for sale, but am happy to help with advice if you want to build a similar project.…
The LGP-30 was a commercial computer, released in 1956. Due to its simple design and relatively low cost, it may be seen as the first “personal computer” – to be used by a single user as their “desk computer”. (It could sit by your desk, and was the size of a desk too.) Designed in the age of vacuum tubes, it needed only 113 tubes in total, of which only 24 were used…
The “real” 9-inch cathode-ray vector monitor is the key component for this project – besides the Asteroids board, of course… A Vectrex game will be the donor for the screen, but some modifications and a custom circuit board are needed to make it work well. Vectrex The Vectrex was a home gaming console launched by General Consumer Electric in 1982. As its unique feature, it…
The Asteroids arcade game keeps a list of the ten best scores, and allows players to enter their initials when they reach a new high score. But it does not store the scores and initials permanently: Whenever the game is powered off, reset, or switched into self-test mode, all score entries are lost. I wanted to add permanent high score storage to my game. But since the Asteroids main board is…
This page has my own files available for download, as well as links to materials available elsewhere. If you come across a broken link, please let me know! Game Manuals and Circuit Diagrams Asteroids Manual, Schematics – various editions available from the ARCade ARChive Asteroids Troubleshooting Encyclopedia Andy's Arcade – great collection of Asteroids documentation Vectrex Service…
Dimensions A Vectrex monitor is very close to half the size of the original monitor in the upright Asteroids cabinet (9" diagonal vs. 19"). The width of the Asteroids circuit board also happens to be quite close to half the width of the full-size Atari cabinet (29.3 cm vs. 64 cm). Nevertheless, I did not opt for an exact half-scale replica of the Asteroids cabinet. I wanted a game that is nicely…
Since the cabinet was built from scratch, I also had to provide the electrical infrastructure to get the Asteroids board going – power supplies, audio amplifier, and marquee illumination. Power supply All power supplies are mounted on a vertical board in the lower front part of the cabinet. The Vectrex brings its own transformer. When removing it from the Vectrex cabinet, be sure to label…
Welcome! Do you enjoy Atari’s old vector arcade games, with the unique glow of a real vector monitor? Maybe even appreciate the discrete vector drawing engine implemented on a baking-tray sized circuit board? But don’t want to install an arcade cabinet the size of a refrigerator in your living room? I built a half-size Asteroids cabinet, using a vintage game circuit board and a real…
A MAME cabinet for vertical games MAME is an open source emulator for arcade games. You can run it on your desktop computer or notebook, but that will not give you quite the right look and feel of an arcade game. Many arcade aficionados build their own custom cabinet around a computer running MAME, complete with arcade-quality joysticks and buttons, and with a case design inspired by typical…
Imagine working at Royal Precision in 1960. This joint venture of General Precision and Royal McBee is a great place to work: With the LGP-30, they are the market leader in the small computer segment – 450 units sold! Only IBM has a better seller, the IBM 650: A larger system, with close to 2000 units in the market. The LGP-30 is a magnetic drum computer. It is awkward to program, because…
Atari’s original PONG arcade game has an interesting design: No microprocessor or program; the whole game logic and signal generation are hard-wired from sixty-some TTL chips. So, when I got my hands on an original 1972 PONG circuit board, I wanted to build a playable cabinet around it, but also display the board with its surprisingly low-integration components. I decided to take my…
The RKS 100-86 “Rollkugel-Steuerung” was the first ball-type mouse, designed by Telefunken in 1968. It was probably the first mouse to be sold commercially, a few years ahead of the Xerox Alto. This page shows photos of my Rollkugel, gives details about the encoders and pinout, and describes an interface which connects the RKS 100-86 to a modern computer. Telefunken’s RKS 100-86…
A custom joystick for the Verticade Most of the old games expect a 4-way joystick, but some are meant to be played with an 8-way stick. But there is definitely no room for dual joysticks in the Verticade – the control panel will be only 20 cm wide. MAME has a feature where you can always use an 8-way stick, and limit the signals sent to the game to pure 4-way.
Hopefully I’ll get around to update this site occasionally. It’s supposed to reflect a reasonably up-to-date state of my project. The most recent changes, as well as developments or questions that have not made it to the regular pages yet, will be summarized here. In the main pages, recent changes will be highlighted like this: New! August 30, 2018 I am re-launching the e-basteln…
The mechanical components of an STM should do three things: Bring the tip into tunneling distance from the sample (coarse approach), keep it there in a stable position (undisturbed by vibrations and thermal drifts), and scan it across the sample with sub-nanometer resolution. This page tries to address all relevant topics, beginning at the center of the STM: Piezo element for scanning motion,…
Since the circuit design is very straightforward, the following sub-sections on Instrument Control and Feedback Loop, Tunneling Current Amplifier, and Piezo Drivers will just give brief circuit descriptions and discuss a few design considerations in more detail. The Miscellaneous section at the end currently just has a few remarks on wiring. The complete schematics are available in PDF format.…
As discussed in detail on the Electronics page, my design uses a digital signal processor (Motorola DSP 56002) to control the STM. The DSP, in turn, is controlled via a serial RS-232 link to a standard PC. The idea is to handle all time-critical tasks - i.e. the X/Y scanning of the STM tip and the feedback loop for controlling the tip height - on the DSP, and run the user interface on the host PC.
This page is still under construction. Since my STM is not producing images yet, I cannot include any images or other ‘application’ results of my own. I have included suggestions for preparing STM tips here, most of which were generously provided by readers of these web pages. Tip preparation Mechanical Sharpening PtIr cutting (adapted from 1998 NanoSurf instructions) This is what I…
STM Budget Item Vendor Price/EURO Price/US$ Mechanics Piezo tube scanner Sensor Technology 74 82 Brass for STM head Koch und Krupitzer 36 40 Machining of STM head Peter Eggerstedt 256 286 Fine-pitch screws and nuts New Focus 83 93 Import duties for screws UPS 22 24 Stepper motor Conrad 2 2 Electronics DSP evaluation board (Motorola DSP56002 EVM) Elektronikladen Detmold 175 195 Power supply…
The main purpose of this section is to ask you about problems I have not figured out yet. I’d sincerely appreciate any hints regarding the following issues - and of course I’d appreciate any questions and remarks you might have about this site! My questions Tip wire Several people have answered my earlier question about recipes for cutting or etching of tips – thanks to all of…
STM Designs Home-built STMs Since I started on my own STM, a number of individual and school or university projects on STM building have become available on the web. While I have not heard about any atomic-resolution STM successfully built by amateurs yet, several designs have reached the stage of producing scanned images. John Alexander's unimorph disk scanner STM An amazingly simple and low-cost…
Editor’s note, August 2018: These instructions were written a long time ago. DanElectro has discontinued the Dan Echo, and their current product lineup looks dubious to me. But it is still worthwhile to buy a used Dan Echo if you can find one! – I have not updated the text below. The various semi-professional conversions are no longer offered. But components for the DIY modification…