The z386 is an open-source FPGA-based CPU that recreates the Intel 80386 architecture by utilizing the original Intel microcode, similar to the earlier z8086 project. It is capable of booting DOS 6 an…
The article summarizes the development of an FPGA-based 80386 core that runs DOS and games at 75 MHz, then shifts focus to analyzing the processor's memory pipeline. It explains that while the 80386's…
The article discusses the 80386 processor's improved protection model, which added paging, a flat 32-bit address space, and Virtual 8086 mode to make protected mode usable after the 80286's unpopular …
The article describes the author's project to build an 80386-compatible processor core in SystemVerilog using original Intel microcode, with real mode operational and over 10,000 test cases passing. I…
The Intel 80386, released in 1985, was the first 32-bit x86 processor, introducing a flat 4GB address space, virtual memory with paging, and an effective protected mode. It significantly improved arit…
The article announces a website redesign for the new year, replacing the Hugo framework with a custom static site generator. It also details the switch from Disqus to Giscus for comments, citing Disqu…
The z8086 is a compact, FPGA-friendly 8086/8088 processor core that runs original Intel microcode by loading a recovered 512x21 ROM, rather than hand-coding individual instructions. Written in about 2…
The article announces the release of an interactive online browser for the 8086 microprocessor's microcode ROM, created by the author after studying the original chip's design. The tool decodes every …
The article describes the release of 486Tang v0.1, a port of the ao486 MiSTer PC core to the Sipeed Tang Console 138K FPGA board, marking the first time this core has been adapted for a non-Altera FPG…
The article describes how the author initially used a softcore CPU to improve FPGA gaming cores on the SNESTang but found it limited by slow performance and high resource usage. After collaborating wi…
The article presents a Python script that automatically adds a title page to PDF documents, specifically designed for use with PDFs generated from ChatGPT conversations. The script uses the `fpdf2` li…
The article discusses a challenge with implementing UART communication in FPGAs when the system clock frequencies are not integer multiples of the desired baud rate, leading to imprecise timing and er…
The article announces the release of MDTang 0.1, a port of the Genesis-MiSTer core for the Tang Mega 138K/138K Pro FPGA boards, bringing Sega Genesis (Mega Drive) emulation to these platforms. It prov…
The article describes the memory system of the GBATang, an FPGA-based Game Boy Advance (GBA) core, which combines FPGA block RAM and external SDRAM to replicate the GBA's diverse memory map. Smaller, …
The article provides practical tips for using Gowin EDA software and Tang FPGA boards (such as the Tang Nano 20K), emphasizing that the free Pro version should be used over the EDU version. It offers …
The article describes the development of GBATang, an FPGA core for the Game Boy Advance (GBA) designed for Tang FPGA boards, which began as a port of the MiSTer GBA core but required significant redes…
The article details the process of building and loading a RISC-V firmware for the SNESTang FPGA project, choosing the minimal RV32I architecture for its small size and mature toolchain. The firmware, …
The article explains the addition of a softcore CPU to the SNESTang 0.3 FPGA project to handle I/O tasks like USB and file systems, which previously consumed valuable FPGA logic space when implemented…
The SNESTang 0.3 project ports the Super Nintendo Entertainment System (SNES) to Tang FPGAs, using a phase-based clock design with a main work clock (wclk) at 10.8 MHz to simplify logic and reduce clo…