3RIC Studio — 65C02 Emulator & Editor

▶ Story ▶ Tutorials ▶ Gallery Insert .woz… Load .PRG… @ $ Speed PC:---- A:-- X:-- Y:-- SP:-- P:-- mode:--- gamepads: detecting… loading wasm…

VIRTUAL KEYBOARD 1983 Apple IIe layout

Caps Lock is shown for layout fidelity; 3RIC input is uppercase-only.

ASSEMBLER sample org $

Pick a sample or write 65C02 assembly, then Assemble & Run.

DEBUGGER running

PC not mapped to assembled source.

breakpoints: none

ASSEMBLED SOURCE (click B to toggle an instruction breakpoint)

Assemble a program to create a source map.

Pause execution to inspect memory.

65C02 emulator core (C++) + WozLib compiled to WebAssembly via Emscripten. Boots the real 512KB ROM, renders Apple-II text/hi-res to the canvas, feeds keystrokes through the memory-mapped keyboard ($C000), maps up to two USB/Bluetooth gamepads through the real SNES/VIA interface, and emulates both the $C030 system speaker and 3RIC slot-4 dual-AY Mockingboard. Click the screen and type, open the Virtual Keyboard on a phone, or pair a controller and press a button. “Boot Disk” boots the bundled 5.25″ floppy (or pick a .woz with “Insert”) through the Disk II ROM at $C600. “Mount SD” enters the DOS shell (prompt “>”) and lists the micro-SD card — load games and programs from there. “Load .PRG” loads a raw program image at the given hex address and runs it, exactly like BRUN FILE.PRG <addr> on the hardware (or deep-link one with ?prg=programs/hello.prg&org=0800). “Speed” sets the CPU clock (native 1× ≈ 1.57 MHz — the 25.175 MHz VGA dot clock ÷ 16; “Max” runs as fast as the frame allows). Sound is enabled by default and starts on the first pointer or keyboard interaction; “Disable Sound” opts out. Other speeds pause and flush audio while the emulated sound hardware continues to run. The Assembler panel assembles 65C02 source in your browser (the same assembler the project uses on the command line) and runs it just like “Load .PRG” — pick a sample, edit it, Assemble & Run (or Ctrl+Enter), and download the resulting .PRG to BRUN on hardware. Hit Share to copy a one-click link to your program (a short ?src= for the built-in samples, or your source inlined in ?code=). Open Debugger to set breakpoints on assembled source lines, pause/continue, step into or over subroutines, and inspect memory. ROM execution is identified from the machine’s ca65 debug map when available.
Building with an AI tool? Point it at llms.txt — a machine-readable 65C02 codegen guide — or see CONTRIBUTING.
New here? Read the story of how 3RIC was built — the breadboard-to-PCB journey, with the YouTube build series.
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