A cycle-accurate hardware simulator reproduces the Commodore 64 ASSY 250407 motherboard pin by pin, letting users lift legs, short pins to ground or +5V, pull chips from sockets, or open passive elements and then observe the resulting display, keyboard behavior and individual signal traces. The simulator uses the PCB netlist and per-pin behavior of every chip so faults are computed from circuit interactions: for example, removing A7 of the 2114 color RAM causes address aliasing that leaves the screen apparently healthy until the leg is restored, and removing the character ROM erases glyph shapes while the CPU and RAM continue. Primary purposes are hands-on learning of C64 internals without risking real hardware and guided fault diagnosis to prioritize desoldering.
Implementation converts a KiCad replica into C tables, uses floooh’s cycle-accurate cores for the 6510, VIC-II, CIAs and SID, and models glue logic, ROMs, DRAMs, color RAM and the PLA with real equations. Every pin drives nets with strength rules, contention resolution and seeded noise; floating nets drift (about 1.4V under TTL loading, otherwise toward 0V) and power faults are modeled per chip. It runs on macOS/Linux with OpenGL, offers a GUI with oscilloscope and a headless CLI for scripted faults and recording, and includes tests for 31 common faults. Limits: slow (≈30-50% real time on modern CPUs), simplified analogs (video output, SID filter, power supply and PLL) and no internal chip cell faults or net bridges yet.
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The Altair 8800 has been reborn as an Arduino-based emulator and kit, allowing hobbyists to build a cycle-accurate replica. The project was inspired by early personal computer history and aims to make the classic machine accessible and affordable. (adwaterandstir.com)
Esp32sim is an open-source emulator that allows users to run ESP32 firmware directly in their browser or locally without hardware or cloud services. It provides a way for developers to test and develop firmware easily and cost-effectively. (github.com)
A calculator helps users determine which Mac models can run specific large language models (LLMs) based on memory and bandwidth. Renting a high-end Mac like the M4 Pro with 64 GB costs around $286/month and can run models such as Llama 3.3 70B at about 5.7 tokens per second. (macyou.co)
Siltop is a system monitor for Apple Silicon Macs that displays real-time watts, clocks, and temperatures in the terminal without requiring sudo or telemetry. It aims to provide a simple and honest monitoring tool for Mac users with Apple chips. (github.com)
A hardware simulator for the Commodore 64 has been developed and shared on GitHub, featuring code, documentation, and testing tools. It enables emulation of the classic computer system for enthusiasts and developers. (github.com)
Brax Wink is a modular, open-source mobile phone designed to prioritize user privacy. It aims to provide a highly secure and customizable device for users concerned about privacy. (braxtech.net)
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