Fenix Guthrie writes that Chris Staecker restored a remarkably well-preserved Digi-Comp 1, the 1963 programmable educational toy computer introduced by E.S.R. The device uses mechanical logic gates programmed with soda-straw-like tubes on sliding rails and spring-loaded levers actuated by a clock switch to compute simple binary functions as a non-Turing-complete state machine reflective of early 1960s computing.
- E.S.R. originally intended to make actual computers before becoming a premier educational toy company in the 1960s
- Staecker'''s restoration used rubber bands and 3D-printed parts to return the toy to working condition
- The machine has 88 states, equivalent to 16,777,216 possible configurations
- Article references successor Digi-Comp II and other vintage ''"sort of''" computers like Geniac
- E.S.R. originally intended to make actual computers before becoming a premier educational toy company in the 1960s
- Staecker'''s restoration used rubber bands and 3D-printed parts to return the toy to working condition
- The machine has 88 states, equivalent to 16,777,216 possible configurations
- Article references successor Digi-Comp II and other vintage ''"sort of''" computers like Geniac
Zoe Skyforest writes about Kek, an emulator developed by vanheusden to bring the influential 16-bit PDP-11/70 minicomputer back to life on modern hardware. The software supports a variety of platforms including Linux, Windows, and microcontrollers like the ESP32 or Teensy 4.1.
- Emulates classic disk drives such as RK05, RL02, RP06, and RP07.
- Supports KW11-L line time clocks and DC-11 serial interfaces.
- Capable of running Unix versions from version 5 through version 7 in multi-user mode.
- Emulates classic disk drives such as RK05, RL02, RP06, and RP07.
- Supports KW11-L line time clocks and DC-11 serial interfaces.
- Capable of running Unix versions from version 5 through version 7 in multi-user mode.
Cabe Atwell writes that the Zilog Z80 is celebrating its 50th anniversary this July. Developed in 1976 by former Intel engineers, it became a dominant 8-bit processor largely due to its instruction compatibility with the existing Intel 8080 software ecosystem. This strategic design allowed manufacturers to adopt more advanced features like built-in DRAM refresh and improved interrupt systems without rewriting their entire codebases.
- Integrated into legendary hardware including Pac-Man arcade cabinets, ZX Spectrum, and TI graphing calculators.
- Launched at a competitive $25 price point to encourage mass market adoption.
- Community-driven silicon replacements are being developed following Littelfuse's cessation of Zilog orders in 2024.
- Integrated into legendary hardware including Pac-Man arcade cabinets, ZX Spectrum, and TI graphing calculators.
- Launched at a competitive $25 price point to encourage mass market adoption.
- Community-driven silicon replacements are being developed following Littelfuse's cessation of Zilog orders in 2024.
A software project that recreates the aesthetic of a 1980s cable community bulletin board for any display, with an emphasis on vintage CRT televisions. It provides a rotating broadcast including time and date, custom messages, fun facts, dad jokes, weather updates via Open-Meteo, and scrolling RSS news headlines in a retro ticker crawl.
Key features include:
A web-based control room for real-time customization of identity, timing, feeds, colors, and message rotation without needing to reload the screen.
Hardware optimization for Raspberry Pi users looking to feed video through HDMI-to-coax modulators or composite AV outputs into old TVs.
Integration with CheerLights to incorporate global color changes directly into the headline crawl.
Support for background music via local audio files and customizable overscan margins for vintage display compatibility.
Key features include:
A web-based control room for real-time customization of identity, timing, feeds, colors, and message rotation without needing to reload the screen.
Hardware optimization for Raspberry Pi users looking to feed video through HDMI-to-coax modulators or composite AV outputs into old TVs.
Integration with CheerLights to incorporate global color changes directly into the headline crawl.
Support for background music via local audio files and customizable overscan margins for vintage display compatibility.
The Computer History Museum in Mountain View has received approximately $14 million from Mad Scientists Anonymous to renovate its computer graphics gallery and preserve the collection of Autodesk co-founder John W. Walker. The funds will support the creation of the John and Roxie Walker Computer Graphics, Music & Art Gallery, scheduled to open in spring 2027. This project aims to showcase the evolution of digital design through storytelling and projection mapping while making Walker’s historical documents available for research via museum archives and a digital portal.
- Renovation of the computer graphics gallery
- Preservation and digitization of John W. Walker's professional collection
- Establishment of an endowment to support future rotating exhibitions
- Renovation of the computer graphics gallery
- Preservation and digitization of John W. Walker's professional collection
- Establishment of an endowment to support future rotating exhibitions
The z386 project aims to implement the Intel 80386 processor core on an FPGA. Recent optimizations have significantly improved its performance, including the implementation of early start memory access and a reduction in branch jump cycles from 9.25 down to six through microcode refinements. These changes resulted in approximately a 39% increase in DOOM benchmark scores, though the project still falls short of original hardware speed and cannot yet boot Windows.
- Implementation of early start memory access for FPGA cores
- Optimization of store queues and branch jump timing
- Significant performance gains in gaming benchmarks
- Implementation of early start memory access for FPGA cores
- Optimization of store queues and branch jump timing
- Significant performance gains in gaming benchmarks
This discussion focuses on the technical efforts to emulate and potentially hardware-reimplement Marvin Minsky’s 2500 computer. Users share resources including a GitHub emulator (`simh/tt2500`) capable of running SITS (Small Incompatible Timesharing System), as well as schematics and SUDS drawings that have been cleared for public viewing. The conversation explores the complexities of recreating the hardware, such as the difficult vector display components, and notes how modern simulation software like "Digital" can be used to model the original design using its existing component libraries.
**Facts Uncovered:**
* **Emulator Availability:** A `simh/tt2500` emulator is available on GitHub for running SITS (Small Incompatible Timesharing System).
* **Documentation:** Schematics and SUDS drawings have been made available to the public following permission requests.
* **Hardware Challenges:** Replicating the vector display is identified as one of the most complicated aspects of a hardware implementation.
* **Obscure Components:** Original parts mentioned include 2507 flip-flops (with shared register enable), an AOI gate (7464), and six-bit 3-state buffer chips.
* **Simulation Tools:** "Digital," a Java-based simulator, is being used to assist in reimplementing the design's components.
**Facts Uncovered:**
* **Emulator Availability:** A `simh/tt2500` emulator is available on GitHub for running SITS (Small Incompatible Timesharing System).
* **Documentation:** Schematics and SUDS drawings have been made available to the public following permission requests.
* **Hardware Challenges:** Replicating the vector display is identified as one of the most complicated aspects of a hardware implementation.
* **Obscure Components:** Original parts mentioned include 2507 flip-flops (with shared register enable), an AOI gate (7464), and six-bit 3-state buffer chips.
* **Simulation Tools:** "Digital," a Java-based simulator, is being used to assist in reimplementing the design's components.
This repository provides an implementation and recreation of the first published version of the Logic Theory Machine, also known as the Logic Theorist. Originally developed by Allen Newell, J. C. Shaw, and Herbert A. Simon in 1956, this program was designed to prove theorems in propositional logic using principles from Principia Mathematica. The project includes a Python-based interpreter for the IPL-I abstract machine language, tools to run the program against historical axioms and theorems, and utilities to analyze generated proofs.
Main components:
Implementation of the 1956 Logic Theory Machine
Propositional logic based on Principia Mathematica
Python interpreter for the IPL-I language
Tools for running simulations and verifying results
Main components:
Implementation of the 1956 Logic Theory Machine
Propositional logic based on Principia Mathematica
Python interpreter for the IPL-I language
Tools for running simulations and verifying results
The May 2026 Obsolescence Guaranteed newsletter highlights significant progress in recreating historical computing environments, most notably through the Arpanet Reconstruction project which now features a functional 35-node simulated network. Major software and hardware updates have arrived for the PiDP series, including new operating systems like Stanford's WAITS for the PiDP-10 and Unix v4 for the PiDP-11. The community continues to expand with enhanced peripheral support for the PiDP-1, new interactive museum concepts, and a growing library of "paleogaming" classics.
* Arpanet Reconstruction: A simulated 35-node network is now online, allowing users to experience the original topology via MIT and Stanford systems.
* PiDP-10 Update: The addition of Stanford's WAITS operating system brings 600MB of historical data and software for exploration.
* PiDP-1 Advancements: New community mods have introduced magnetic drum storage, light pen support, and a wide array of peripheral options.
* PiDP-11 Milestones: Unix v4 has been successfully recovered and is now bootable on the PiDP-11 platform.
* Enigma Touch: A new cased version featuring high-quality woodworking and historically accurate leather straps and metal clips is available.
* Arpanet Reconstruction: A simulated 35-node network is now online, allowing users to experience the original topology via MIT and Stanford systems.
* PiDP-10 Update: The addition of Stanford's WAITS operating system brings 600MB of historical data and software for exploration.
* PiDP-1 Advancements: New community mods have introduced magnetic drum storage, light pen support, and a wide array of peripheral options.
* PiDP-11 Milestones: Unix v4 has been successfully recovered and is now bootable on the PiDP-11 platform.
* Enigma Touch: A new cased version featuring high-quality woodworking and historically accurate leather straps and metal clips is available.
