TRX64 vs Z64K

TRX64 is a free, open-source Rust runtime for cycle-accurate emulation of the Commodore 64, 1541, and 1581. Its reverse-engineering tools include rewind, byte-exact reverse stepping, write tracking, observers, traces, marks, and sandboxes. A daemon exposes JSON-RPC 2.0 over WebSocket, with project capabilities available through JSON-RPC methods. Users can work with trx64cli, a terminal cockpit with an optional native emulator window, or C64RE, a browser-based reverse-engineering workbench. The daemon supports c64, u64, and 128 machine selections, with PAL and NTSC C64 models documented. Media and hardware support includes D64/G64 disks in 1541 drives, D81 disks in 1581 drives, cartridge types, REU, GeoRAM, and the Ultimate Command Interface. It also supports machine snapshots, reverse-debug buffers, trace logs, and VICE .vsf snapshot conversion. Releases are available for Linux, macOS, and Windows, with builds for x86_64 and arm64 where listed. C64 ROMs, including the 1581 DOS ROM, are not included and must be supplied separately.

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.