Altirra vs Felix

Altirra is a Windows emulator for 8-bit Atari computers, covering the Atari 400/800, 1200XL, 600/800XL, 130XE, XEGS and 5200. It provides cycle-exact handling of documented hardware and models undocumented behavior, including DMA timing and undocumented 6502 instructions. Supported files include ATR, ATX, ATZ, DCM, XFD, PRO, ARC, BAS, ROM, BIN, A52, CAS and SAP. Reimplemented operating-system, BASIC and handler ROMs are included, while real Atari ROM images can be supplied for compatibility. The emulator models memory and cartridge expansions, PBI devices, modems and 65C02/65C816 accelerators. Disk options include accelerated loading, realistic timing, sounds and drive CPU emulation. Its debugger offers source stepping, breakpoints, watchpoints, history and profiling. Recording, a cheat trainer, disk browsing and text copy/paste are also included. Altirra is free under GPL version 2 for Windows 7 or later.

Felix is a free Atari Lynx emulator distributed as a public GitHub repository under the MIT license. It currently builds only under Windows, with documented build routes through Visual Studio 2022 or command-line CMake; both require Visual Studio 2022, Git, and CMake. The README says it is expected to work in Wine, Parallels, and similar environments. Version 0.5.0 introduced a simple graphical interface, redefinable key mapping, and basic gamepad support. Release notes also list Lua debugging facilities, a monitor window, and commands for dumping WAV and VGM audio. Lua libraries for string, os, math, and table are included. The latest listed release is 0.6.4. Known issues in version 0.6.0 include hangs in Awesome Golf and Scrapyard Dog, crackling from audio/video synchronization, and debugging features that remain imperfect. The project is maintained through the laoo account, whose profile names Waldemar Pawlaszek and lists Wrocław.