Apple //e
A cycle-accurate Apple IIe Enhanced emulator running entirely in your browser. Built with C++ compiled to WebAssembly, with WebGL rendering and Web Audio for authentic sound.
Key Features
Cycle-Accurate 65C02
Full CMOS 65C02 CPU emulation at 1.023 MHz with per-instruction cycle counting, decimal mode, and proper page-crossing penalties.
6 Video Modes
Text 40/80, LoRes, HiRes, Double LoRes, and Double HiRes with NTSC artifact colors, per-scanline rendering, and mid-frame mode switching.
Mockingboard Sound
Dual AY-3-8910 chips with stereo output, plus the built-in 1-bit speaker with anti-aliased sample generation for authentic audio.
Disk II & SmartPort
Full Disk II controller with GCR encoding and Logic State Sequencer. Supports DSK, DO, PO, NIB, and WOZ formats with write capability. SmartPort hard drives for HDV/2MG images.
CRT Shader Effects
Configurable WebGL CRT effects including scanlines, curvature, phosphor glow, vignette, NTSC fringing, flicker, and monochrome modes (green, amber, white).
Save States
Autosave every 5 seconds plus 5 manual save slots. Full state serialization including CPU, 128KB RAM, disk modifications, and debugger state.
Expansion Cards
7 expansion slots with hot-swappable cards, faithfully emulating the Apple IIe's legendary expandability.
Disk II Controller
Two 5.25" floppy drives with stepper motor emulation, GCR encoding/decoding, and support for DSK, DO, PO, NIB, and WOZ disk formats.
Mockingboard
Dual AY-3-8910 sound chips with dual VIA 6522 timers for stereo sound across 6 tone channels and 2 noise channels.
Thunderclock Plus
Real-time clock providing ProDOS-compatible date and time services to the emulated system.
Z-80 SoftCard
Full Z80 co-processor emulation at 2.041 MHz with hardware address translation, enabling CP/M software on the Apple II.
SmartPort
Hard drive controller supporting 2 block devices with HDV, PO, and 2MG image formats for high-capacity storage.
Super Serial Card
ACIA 6551 serial communication with WebSocket-to-TCP proxy and Hayes modem emulation for network connectivity.
Developer & Debug Tools
A comprehensive suite of tools for exploring, debugging, and developing software for the Apple IIe.
CPU Debugger
Breakpoints, watchpoints, step-over/out, conditional expressions, and beam breakpoints for position-based debugging.
Memory Browser
Hex/ASCII view of the full 128KB address space with real-time memory heat map tracking read/write access patterns.
File Explorer
Browse DOS 3.3 and ProDOS filesystems. View BASIC programs with syntax highlighting, disassemble binaries with clickable cross-references.
Assembler & Disassembler
Built-in 65C02 assembler with Merlin syntax and a recursive-descent disassembler with flow analysis and symbol resolution.
BASIC Editor
Full Applesoft BASIC editor with tokenizer/detokenizer, statement breakpoints, variable inspector, and line heat map.
Soft Switch Monitor
Real-time visibility into all Apple IIe soft switches, stack viewer, zero page watch, and instruction trace logging.
Technical Architecture
WebAssembly Core
The entire emulation core is written in C++ and compiled to WebAssembly via Emscripten with full LTO optimisation. The CPU, MMU, video, audio, and all expansion cards run as native-speed WASM.
Audio-Driven Timing
The master clock is driven by Web Audio API at 48 kHz rather than requestAnimationFrame. This provides precise timing, background tab support, and synchronized audio/video with no drift.
Web Worker Architecture
The WASM emulator runs in a dedicated Web Worker via an ES6 Proxy wrapper, keeping the UI responsive. Fire-and-forget calls skip waiting for responses while batch queries collapse into single round-trips.
WebGL Rendering
Per-scanline progressive rendering catches mid-frame video mode changes. The framebuffer is uploaded as a WebGL texture and processed through a configurable CRT shader pipeline.
Agent Integration
Model Context Protocol
The emulator exposes a full MCP server and AG-UI event protocol, allowing LLMs to programmatically control the emulator. Run multiple browser tabs simultaneously, each with a unique name, and issue broadcast or targeted commands for automated testing, exploration, and development workflows.
Ready to explore the Apple //e?
No installation required. Just click and start computing.