Frodo vs VirtualC64

Frodo is a free, portable Commodore 64 emulator for Linux, macOS, and Windows. It focuses on reproducing special graphical effects from the C64 and supports disk and tape software, many game cartridges, and formats including D64, G64, T64, TAP, X64, and LYNX. It offers a cycle-exact regular mode and Frodo Lite, a less compatible version intended to run better on slower machines. The official site lists V4.5, which adds Datasette TAP emulation and support for banked cartridges including Ocean, Fun Play, Power Play, Super Games, and Simons' BASIC. TAP emulation is unavailable in Frodo Lite. V4.5 can auto-start disk and tape images, cartridges, and C64 BASIC program files from the command line. Frodo can detect connected controllers for C64 joystick ports and map additional buttons to C64 keys. Display settings include windowed or fullscreen mode and an initial window size. The V4.5 snapshot format changed, so it cannot read snapshots from earlier versions. Frodo is listed under GPL-2.0.

VirtualC64 turns an Apple Macintosh into a Commodore 64 emulator, supporting PAL and NTSC systems with emphasis on PAL accuracy and cycle-accurate emulation. It includes a built-in debugger and supports the PAL C64, NTSC C64, C64 II PAL, and C64 II NTSC variants. Media formats include D64, T64, PRG, P00, G64, TAP, and CRT. Joystick input can come from the keyboard or an external USB device; named options include Sony DualShock 4 controllers and the RetroFun! USB adapter for original Commodore joysticks. VirtualC64 is free and open source under the GNU General Public License, while its CPU core uses the MIT license. The core is designed for WebAssembly and can run in a browser, although macOS is the listed supported platform. On first launch, users are prompted to add four ROM images, which are not pre-installed because their copyright status is unclear. Recent versions include free ROM replacements from the Mega65 project, installable through the ROM configuration panel.