Stefan ArentzandClaude Fable 5
f81a806906
Completes the CPU core port:
- ins.rs: the 65C02 override handlers ((zp) modes, BRA, STZ, PHX/PHY/
PLX/PLY, TRB/TSB, RMB/SMB, BBR/BBS, INC/DEC A, BIT imm/zpgx/absx,
JMP (abs,X)) and the override table transcribed verbatim from
instructions_65C02 — including its 1-cycle NOPs and the stray 0x03
opcode fields. The table is overlaid onto the 6502 table once, the
Rust version of cpu_initialize()'s back-fill. C's arity-cast NOPs
become explicit nop_byte/nop_word wrappers.
- fmt.rs: cpu_format_state, cpu_format_stack, and the disassembler
from fmt.c, bugs preserved (0x9c prints JMP; BBR/BBS targets are
computed from pc+2).
- tests/dormann.rs: dormann_65c02 passes at $24a8 after 65,094,140
cycles — exactly the C emulator's count.
- Golden-trace harness: scripts/gen-golden-trace.{c,sh} builds a
capture program against the unmodified C sources and records the
first 100k instructions of the functional test as normalized
'PC A X Y SP P' lines; checked in gzipped. trace_compare.rs replays
it on the Rust core and reports the first divergent instruction
(currently: zero divergence). flate2 is a dev-dependency only.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Emulated Woz Machine
Introduction
Two years ago between christmas and new year I wrote a tiny and incomplete 6502 emulator and turned it into an original Apple 1 emulator. It was a fun and nostalgic project to work on. I grew up with the Apple II and never had a change to see an Apple 1 in action.
A few weeks ago I decided to pick this project up again. I am extremely motivated to turn this into a high quality emulator that supports the Apple 1, Replica 1, Apple ][+ and Apple IIe. Some of that work is really close to being finished, other work will take many months of spare time hacking.
Note: A Rust rewrite is in progress; see REWRITE.md. The C build below remains the primary build until the rewrite completes.
Goals & Status
Here are some of the things I want to accomplish for each emulated machine:
CPU Emulator
6502 support65C02 supportTracing facility- Debugger
- Speed throttling
Apple 1
8K / 6502 / Classic ROM
Terminal based emulationClassic display emulation (SDL based)- Cassette interface
Replica 1
32K / 65C02 / KRUSADER ROM
Terminal based emulationClassic display emulation (SDL based)- Cassette interface
- CFFA1 Support
Apple ][+
48K / 6502
Basic Apple ][+ architecture implementation - In progressDisk II emulation - In progressDisplay Emulation - 40 Column modeDisplay Emulation - Low resolution graphicsApple Language CardJoystick Support- Audio Support
- Display Emulation - High resolution graphics - Mostly works.
Building the emulator
cd src
make
Running the emulator
From the command line:
./src/ewm two --color --drive1 disks/DOS33-SamplePrograms.dsk