DOS Wasm X vs DOSVisor

DOS Wasm X is a free, browser-based DOS emulator built around the DOSBox-X codebase and using WebAssembly. It provides virtual hard drive choices of 512 MB, 1 GB, or 2 GB and RAM choices of 32 MB, 64 MB, or 128 MB. The browser stores the drive so users can return later, and it can be exported as an image for local saving. Supported file types include ISO, ZIP, BIN, CUE, IMG, and 7z; users can import and export files and change a CD while the emulator is running. Controls include mobile mode, an on-screen keyboard, gamepad support, full screen, zoom, mouse capture, CPU speed and emulator time settings, and pause and resume. Audio, dark mode, and resolution resizing are also listed. Windows 95 or Windows 98 can be installed with the user's own Windows copy and ISO. The project can be hosted on a web server by copying the dist folder or run in a container using its Docker command. Before leaving after using Windows, shut it down within the guest system to save drive changes.

DOSVisor is a Windows project that runs some MS-DOS programs in a virtualized 16-bit real-mode environment using the Windows Hypervisor Platform API. It is presented as a demonstration of that API rather than a complete DOS emulator. Hardware virtualization handles the CPU, while software emulates the DOS layer. A custom Interrupt Vector Table uses CPUID instructions to trigger VM exits and intercept DOS interrupts. DOSVisor captures I/O requests but supports only a small set of common requests. Timing support includes the BIOS counter, RAM refresh toggle bit, system clock, RTC registers, clock interrupts, and DOS current-time calls; the 8253 PIT timer is not fully implemented. Keyboard handling monitors state, keeps a simple buffer, and passes input through interrupts. Basic terminal commands support simple text-based games and other basic programs. BIOS data areas and the Program Segment Prefix are allocated but mostly unpopulated. The free public repository contains bin and src directories, with no releases or packages listed.