DOSVisor vs UniPCemu

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.

UniPCemu is a free, downloadable x86 emulator for classic PC software. Its main listing covers Windows and Android, with additional builds mentioned for PSP, Nintendo Switch and PS Vita. The emulator models CPU generations from the 8086/8088 through Pentium II, and drivers can provide software floating-point emulation. Hardware choices are configurable: graphics range from IBM MDA to ET4000/W32 SVGA, while sound options run from the PC speaker to Sound Blaster 2.0. It supports MS-DOS targets, DSK, IMD, CUE, IMG and IMA disk images, gamepads, audio CDs, mouse and keyboard, PSP-style controls and touch input. Windows MIDI passthrough is available. Windows server builds can use TCP to simulate SLIP or PPP connections, with multi-client and protocol support plus IP-based access controls. Android data is not backed up automatically and may be deleted on uninstall. Users provide ROMs and disk images. Windows server builds require WinPcap-compatible software.