Breadbin466 vs Z64K

Breadbin466 is a free Commodore 64 emulator written in Rust, focused on modeling one PAL Assy 250466 machine. Its cycle-driven emulation covers the MOS 6510 CPU and VIC-II video timing and generation, including bus arbitration. The SID sound model draws on a physical datecode 2286 chip and models oscillator, DAC, mixing, and filter behavior. Its Commodore 1541 drive emulation includes a separate CPU, VIAs, mechanics, GCR read channel, IEC communication, fastloaders, and protected-disk behavior. Other modeled hardware includes CIA interfaces, a 1351 proportional mouse, a Datassette with TAP playback and recording, cartridges, and a 512 KB REU. It supports D64, G64, NIB, NBZ, and D7Z disk images, with tools for image creation, conversion, and space reclamation. The integrated debugger provides breakpoints, disassembly, history, and configurable tracing. Native menus and Inspector windows are provided on macOS, Windows, and Linux. Version 0.99.0 is described as feature-complete, with broader testing still remaining before 1.0.

Z64K emulates the Commodore 128, Commodore 64, Spectrum 48/128K, VIC 20, and Atari 2600, with pixel-exact emulation described by its maker. It runs through Java on Windows, macOS, and Linux and requires JRE 8 or later. Downloads include the main JAR, command-line files, a changelog, and a quick guide. Controls include fullscreen, clipboard text copy and paste, reset, mouse capture, and warp mode. C128 controls include switching display modes and toggling the second display; extended keys and function-key mappings are also described. The built-in debugger and SID Analyzer provide additional tools, with the analyzer offering waveform, envelope, oscillator, and combined display modes. Supported disk and tape formats include D64, D71, G64, G71, IMD, and CRT. The Virtual FS device is experimental, and its scratch command simulates deletion without removing files from the host system. Linux users might need to adjust the JAR's permissions to allow execution. Z64K is free.