🕹️ Pico-286 Project

The Pico-286 project is an endeavor to emulate a classic PC system, reminiscent of late 80s and early 90s computers, on the Raspberry Pi Pico (RP2040/RP2350 microcontroller). It aims to provide a lightweight and educational platform for experiencing retro computing and understanding low-level system emulation. 🖥️✨

⭐ Key Features

• 🧠 8086/8088/80186/286 CPU Emulation: At its core, the project emulates an Intel cpu up to 286 family.
• 🌐 Cross-platform: Can be built for Raspberry Pi Pico and Windows.
• 🔌 Retro Peripheral Emulation: Includes support for common peripherals from the era.
• 🎨 Text and Graphics Modes: Supports various display modes common in early PCs.
• 🔊 Sound Emulation: Recreates sound capabilities of classic sound cards.
• 🍓 Designed for Raspberry Pi Pico: Optimized for the RP2040/RP2350 with minimal external components.

🎮 Supported Hardware Emulations

🧠 CPU Emulation

• Intel 8086/8088/80186/286 processor family

🎵 Sound Card Emulations

• 📢 PC Speaker (System Beeper): Authentic emulation of the original PC's internal speaker system
• 🎚️ Covox Speech Thing: Compatible emulation of the simple parallel port DAC
• 🎭 Disney Sound Source (DSS): Emulation of the popular parallel port digital audio device
• 🎹 Adlib / Sound Blaster (OPL2 FM Synthesis): High-quality emulation of the Yamaha OPL2 chipset for classic FM music and sound effects.
• 🔊 Sound Blaster (Digital Audio): Support for Sound Blaster's digital sound capabilities, including DMA-based playback.
• 🎼 MPU-401 (MIDI Interface with General MIDI Synthesizer): Provides a MIDI interface and includes an integrated General MIDI (GM) software synthesizer, allowing playback of GM scores without external MIDI hardware. This is a key feature for many later DOS games.
• 📢 Tandy 3-voice / PCjr (SN76489 PSG): Emulation of the Texas Instruments SN76489 Programmable Sound Generator.
• 🎮 Creative Music System / Game Blaster (CMS/GameBlaster): Emulation of the dual Philips SAA1099 based sound card.

🖼️ Graphics Card Emulations

📝 Text Modes (Common to All Graphics Cards)

All graphics card emulations support standard text display modes for character-based applications:

• 16 foreground colors with 8 background colors
• Full color attribute support including blinking text

📝 Standard Text Modes:

• 80×25 Text Mode: Standard 80 columns by 25 rows character display
• 40×25 Text Mode: Lower resolution 40 columns by 25 rows display

🚀 Advanced CGA Text Modes (8088 MPH Demo Techniques):

• 🎨 160×100×16 Text Mode: Ultra-low resolution high-color text mode
  • Revolutionary technique showcased in the famous "8088 MPH" demo by Hornet
  • 16 simultaneous colors from CGA palette in text mode
  • Achieved through advanced CGA register manipulation and timing tricks
  • Demonstrates the hidden capabilities of original CGA hardware
• 🌈 160×200×16 Text Mode: Enhanced color text mode
  • Extended version of the 8088 MPH technique with double vertical resolution
  • Full 16-color support in what appears to be a text mode
  • Pushes CGA hardware beyond its original specifications
  • Compatible with software that uses advanced CGA programming techniques

🎨 CGA (Color Graphics Adapter)

The CGA emulation provides authentic IBM Color Graphics Adapter functionality, supporting the classic early PC graphics modes:

🎮 Graphics Modes:

• 🌈 320×200×4 Colors: Standard CGA graphics mode with selectable color palettes
• ⚫⚪ 640×200×2 Colors: High-resolution monochrome mode (typically black and white)
• 📺 Composite Color Mode (160×200×16): Emulates the artifact colors produced by CGA when connected to composite monitors, creating additional color combinations through NTSC color bleeding effects

📊 HGC (Hercules Graphics Card)

The Hercules Graphics Card emulation recreates the popular monochrome high-resolution graphics standard:

🖥️ Graphics Mode:

• ⚫⚪ 720×348×2 Colors: High-resolution monochrome graphics mode

🖥️ TGA (Tandy Graphics Adapter)

The Tandy Graphics Adapter emulation recreates the enhanced graphics capabilities of Tandy 1000 series computers:

🚀 Enhanced Graphics Modes:

• 🎨 160×200×16 Colors: Low-resolution mode with full 16-color palette
• 🌈 320×200×16 Colors: Medium-resolution mode with 16 simultaneous colors from a larger palette
• ✨ 640×200×16 Colors: High-resolution mode with 16-color support

🖼️ VGA (Video Graphics Array)

The VGA emulation provides comprehensive Video Graphics Array support with multiple advanced modes:

📊 Standard VGA Modes:

• 🎮 320×200×256 Colors: Mode 13h - the famous "Mode X" used by many DOS games
• 🖥️ 640×480×16 Colors: Standard VGA high-resolution mode
• 📺 720×480×16 Colors: Extended VGA mode
• 📝 Text modes: 80×25 and 80×50 with enhanced character sets

🔧 Hardware Configuration

The Pico-286 emulator is designed to run on Raspberry Pi Pico (RP2040) based hardware. 🍓

🎛️ Supported Components

• ⌨️ PS/2 keyboard and mouse
• 💾 SD card for storage
• 📺 VGA and HDMI for video output
• 🔊 Audio output
• 🎮 NES gamepad

🏗️ Minimal Configuration

• 🍓 Raspberry Pi Pico (RP2040)
• 🧠 External PSRAM chip (minimum 8MB recommended for broader compatibility) connected via SPI.

🚀 Recommended Configuration for Maximum Performance

• 🍓 Raspberry Pi Pico 2 (RP2350)
• ⚡ QSPI PSRAM for faster memory access.

🛠️ Development Platform

• This project primarily uses the MURMULATOR dev board as its hardware base. This board provides an RP2040, PSRAM, and various peripherals suitable for the emulator's development and testing. 🎯

🔨 Building and Getting Started

Information on how to build and run the Pico-286 emulator will be provided in a separate document or a Wiki page (link to be added). 📚

🤝 Contributing

Contributions to the Pico-286 project are welcome! Please refer to the CONTRIBUTING.md file (to be created) for guidelines. 💪

📄 License

The Pico-286 project is typically released under an open-source license (e.g., MIT, GPL). The specific license details will be found in a LICENSE file in the repository. (To be confirmed by checking repository) ⚖️