Projects sharing features with Bitwise

GHDL is a compiler and simulator for VHDL hardware descriptions. It functions as a multi-pass analysis elaborator that resolves design hierarchies and dependencies to prepare hardware descriptions for simulation or synthesis. The project transforms VHDL source code into executable binaries for high-speed digital design verification and serves as a synthesis tool that converts descriptions into structural netlists compatible with vendor or open-source flows. It also implements the Language Server Protocol to provide static analysis, autocomplete, and code navigation for VHDL files. The toolse

picorv32 is a size-optimized RISC-V CPU core and synthesizable processor IP designed for integration into FPGA and ASIC hardware designs. It serves as an open-source CPU architecture and embedded system-on-chip component that implements a standard RISC-V instruction set. The design features a modular architecture that allows for the integration of external coprocessors to implement custom non-branching instructions. It includes a parameterized integer unit with configurable multiplication and division cores to balance performance against total logic gate count. The project covers a broad ran

This project is a collection of technical documentation and guides designed as a computer architecture explainer. It provides educational resources on how processors and operating systems execute programs, focusing on the fetch-execute cycle and the fundamental relationship between hardware and the kernel. The documentation covers a wide range of low-level system operations, including detailed guides on the executable and linkable binary format, virtual memory management, and kernel-level operations. It specifically explores the mechanics of CPU scheduling, preemptive multitasking, and the us

PyBoy is a programmable Game Boy emulator and hardware simulation framework written in Python. It functions as an emulation engine that allows users to execute original handheld software while providing a programmatic interface to control, probe, and automate game execution. The project is specifically designed as a reinforcement learning environment, exposing emulator states and controls to facilitate the training of machine learning agents. It distinguishes itself by providing tools for game area mapping and the extraction of simplified 2D screen representations and collision maps to suppor

SimpleNES is a C++ application that simulates original Nintendo Entertainment System hardware to run legacy games on modern computers. It functions as a hardware simulator and retro gaming emulator designed to execute classic game ROMs by recreating the original console environment through software. The system implements a software version of the 6502 CPU and picture processing unit to render retro game video and audio. It recreates 8-bit console architecture to ensure the execution of original game ROMs. The project covers low-level hardware simulation, including cycle-accurate CPU emulatio

86Box is a low-level x86 hardware emulator and vintage PC simulator designed to replicate early IBM PC compatibles. It provides virtualized environments for executing legacy operating systems, such as MS-DOS and early versions of Windows, by simulating processors and system designs ranging from the 8086 through the Pentium era. The project distinguishes itself through cycle-accurate processor simulation and high-fidelity hardware emulation. This includes the ability to route retro MIDI audio data to emulated hardware modules or external synthesizers to achieve authentic audio playback from le

This project is an open-source computer-aided design toolchain designed for the synthesis, placement, and routing of hardware designs onto programmable logic architectures. It serves as a comprehensive framework for research and development, enabling the transformation of hardware description language designs into optimized netlists and physical implementation files. By providing a modular pipeline, the system facilitates the entire flow from initial logic synthesis to the generation of configuration data for programmable hardware devices. The toolchain distinguishes itself through its focus

Tiny-gpu is an educational hardware emulator designed to model the fundamental operations of a graphics processing unit. It provides a software environment that simulates hardware data flow and parallel computing logic, allowing users to visualize the internal execution cycles and memory structures characteristic of graphics hardware. The project distinguishes itself by implementing a cycle-accurate execution model that tracks the progression of operations through discrete processing steps. It utilizes a fixed-function pipeline to process geometric data through sequential transformation and r

This project is a tutorial and framework for building a low-level, bare-metal operating system from scratch using the Rust language. It focuses on ARMv8 kernel development specifically for the Raspberry Pi 3, providing the resources necessary to implement a monolithic kernel that runs directly on hardware without an underlying operating system. The project distinguishes itself by providing a complete embedded cross-compilation suite within a containerized environment to ensure consistent builds. It includes a dedicated kernel deployer that uses a serial interface and chainloader to load and b

Chips is a modular, header-only C library framework designed for building cycle-accurate hardware simulators and replicating historical eight-bit computing architectures. It provides the foundational components necessary to construct complete vintage systems by integrating individual emulated microprocessors and peripheral chips. The framework distinguishes itself through a component-based architecture where hardware modules are implemented as standalone headers that can be wired together to form complex systems. It models hardware interactions at a low level, utilizing pin-level signal emula

mGBA is a high-accuracy Game Boy Advance emulator and hardware-level debugger designed to run handheld console ROMs on modern computers. It serves as a scriptable emulation environment that allows for the execution of portable hardware software and the simulation of associated peripherals. The project distinguishes itself through its focus on technical analysis, providing a suite of tools for retro game debugging and game logic inspection. It includes a host-client debug protocol that enables external debugger connectivity via TCP socket communication and an event-driven scripting engine for

This project is a bare-metal operating system developed for ARM64 architecture. It serves as a low-level implementation of kernel engineering, focusing on the fundamental construction of an OS from the hardware level up. The system is distinguished by its comprehensive approach to ARM64 processor control, featuring a red-black tree task scheduler and a hierarchical page table system for virtual memory management. It implements a sophisticated privilege model that handles transitions between kernel and user modes, ensuring process isolation through address space splitting and exception level m

This project is a freestanding kernel written in Rust that boots on x86 hardware without a standard library. It serves as a low-level system implementation focusing on the creation of a bare metal operating system. The system implements a bootable disk image toolchain that transforms source code into binaries compatible with a bootloader. It features a custom memory allocator for dynamic memory management and an x86 kernel implementation that includes paging, interrupt handling, and VGA text mode. The project covers several core capability areas, including low-level memory management through

This project is a comprehensive technical interview preparation resource and computer science interview guide. It serves as an educational reference for developers to study core software engineering fundamentals and common coding patterns required for employment screenings. The repository provides detailed guides and references covering data structures and algorithms, networking and security, operating systems, and web development. It specifically focuses on the implementation and complexity analysis of sorting, searching, and graph algorithms. The material encompasses a wide breadth of comp

Redox is a POSIX-compliant, microkernel-based operating system written entirely in Rust. By utilizing a memory-safe language for the kernel and all system components, the project eliminates common vulnerabilities such as buffer overflows and use-after-free errors. Its architecture relies on a minimal kernel that manages only essential hardware and process isolation, delegating all other system services to unprivileged user-space processes. The system distinguishes itself through a modular design where hardware drivers and system services run as independent user-space daemons, allowing them to

This project is a monolithic operating system kernel designed to serve as the foundational software layer for diverse computing architectures and embedded platforms. It manages core system services, including processor scheduling, memory allocation, and hardware resource distribution, to facilitate communication between user applications and physical hardware. The kernel utilizes a hardware abstraction layer and platform-specific device trees to ensure consistent operation across a wide variety of processors and specialized computing devices. It supports dynamic functionality through loadable

Open-smartwatch-os is an operating system designed for resource-constrained wearable devices. It provides a development and testing environment that allows developers to build, validate, and debug firmware for smartwatches within a simulated desktop environment before deploying to physical hardware. The project distinguishes itself through a comprehensive suite of tools for hardware emulation and remote diagnostics. By utilizing a hardware abstraction layer and modular driver architecture, it decouples core system logic from specific physical components. This enables developers to run the ope

This is a practical, step-by-step guide to Linux system administration, command-line usage, and development environment setup, written from the perspective of a Java developer. The tutorial is structured as a sequence of terminal commands with explanations, teaching system administration through direct modification of plain-text configuration files. It provides separate workflows for CentOS, Ubuntu, and Kali Linux, covering both yum and apt package managers with equivalent commands for each operation. The guide emphasizes a security-first workflow, walking through firewall configuration, SSH

The Linux kernel is a monolithic operating system core that manages hardware resources, memory, and process scheduling across diverse computing architectures. It provides a standardized, POSIX-compliant environment for application execution while maintaining a modular driver framework that allows for the dynamic loading and removal of hardware interfaces. The project is distinguished by its high-performance concurrency toolkit, which utilizes lockless synchronization primitives and read-copy-update mechanisms to manage shared data access in multi-core environments. It incorporates a comprehen

This project is an educational resource and technical reference for building operating systems from scratch. It provides a comprehensive guide to mastering x86 architecture and implementing core kernel components by writing code that executes directly on hardware without the support of standard libraries or operating system abstractions. The materials focus on low-level systems engineering, teaching users how to interpret technical datasheets to manage hardware resources. It covers the fundamental mechanics of bare-metal programming, including the use of assembly language to define execution

LiteX is an FPGA SoC development suite and SoC builder framework used to programmatically design system-on-chips. It provides a hardware description toolchain that uses a scriptable framework to define hardware layouts and automate the generation of hardware description language code. The project distinguishes itself by orchestrating multiple vendor and open-source toolchains to synthesize digital logic and generate deployable bitstreams. It supports multi-language logic integration, allowing disparate hardware description languages to be combined into a single project. The framework covers

Dolphin is a software environment that simulates GameCube and Wii console hardware, allowing users to execute game discs and digital software on modern computing platforms. It functions by translating original console processor instructions into native host machine code at runtime and intercepting low-level graphics commands to render them through modern graphics APIs. The project distinguishes itself through a comprehensive netplay engine that enables online multiplayer for local games by synchronizing game states and input timing across remote instances. This system enforces deterministic e

Computerraria is a digital logic circuit simulator and computer architecture educational tool. It provides a sandbox environment for building and testing functional computer systems by connecting modular logic gates and electronic wires. The project serves as a RISC-V architecture simulator that executes RV32I machine code using virtualized hardware components. It includes a virtualized CPU toolchain that uses containerized systems to compile source code into binary formats compatible with these custom processor architectures. The system covers digital logic circuit design and RISC-V ISA sim

MAME is a vintage hardware emulation platform designed to recreate the circuitry of arcade games, computers, and consoles to run original software on modern devices. It functions as a retro gaming preservation framework for managing, verifying, and archiving ROM sets and disk images to ensure long-term software accessibility. The project features a system debugging tool for inspecting emulated memory, CPU registers, and execution flow via breakpoints and disassembly. It also includes a Lua-based automation layer that exposes core system state and hardware controls for custom behavior and anal

xv6 is a Unix-like educational operating system designed for teaching kernel concepts. It is implemented as an instructional kernel for x86 and RISC-V architectures, featuring a virtual memory manager and support for symmetric multiprocessing. The system is designed to demonstrate core OS principles through a simplified re-implementation of Unix Version 6. It provides a controlled environment for studying system calls, trap handling, and process lifecycles. Its capability surface covers process management, including scheduling and context switching, and memory management via page tables for

XNU is a hybrid operating system kernel that combines a microkernel architecture with a monolithic layer for system services. It provides a foundation for operating system development, incorporating standardized system-call interfaces, a modular device driver framework, and mandatory access control security. The architecture features a Mach-based microkernel and a BSD-based monolithic layer. It utilizes a message-passing inter-process communication bus for secure data exchange between isolated kernel components and user-space processes, alongside an object-oriented driver framework that decou

Clash is a functional hardware compiler and hardware description language compiler that translates strongly typed functional programs written in Haskell into synthesizable VHDL, Verilog, and SystemVerilog code. It serves as a development tool allowing digital designers to write hardware descriptions in functional languages and compile them directly to FPGA targets and physical netlists. The compilation infrastructure covers structural hardware compilation, including graph-based code normalization, functional language translation, and netlist generation. It features type-level clock domain saf