A7800 vs Test7800

A7800 is a free, open-source Atari 7800 emulator and a fork of the MAME Atari 7800 driver. It runs on Android, Linux, macOS, and Windows; version 5.2 lists 64-bit x64 builds for Linux, macOS, and Windows. The emulator supports Proline and VCS joysticks, lightguns, paddles, driving controllers, keypads, Trak-Balls, Amiga mice, and ST mice. Its listed technical work includes improved MARIA DMA timing with accurate DMA-hole penalties, a RIOT emulation fix, POKEY sound changes, and SALLY and MARIA performance adjustments. Users can choose palettes and enhanced screen options. BIOS files are optional and not required. A7800 keeps MAME compatibility and syntax, allowing reuse of MAME configuration files and front ends. Developer targets can display DMA usage per scanline. The repository is offered under GNU GPL version 2 or later, and the license provides no warranty. The project labels v5.2 as its latest release, including corrections to the POKEY poly9 sequence and initial state.

Test7800 is an experimental Atari 7800 emulator for playing many available 7800 ROM files. It supports flat .a78 ROMs, several bankswitching SuperGame ROMs, and ELF cartridges with an embedded ARM chip. Its emulation includes 6502, TIA, RIOT, and ARM components taken from Gopher2600; the MARIA implementation is new to this project. POKEY and many of its layouts are supported. Players can use a keyboard or gamepad, with a mouse for paddle and trackball input. QuadTari mode supports up to four joystick players, with assignments configurable through -players. An optional overlay displays MARIA state, and the -tv option selects PAL instead of the default NTSC BIOS. Test7800 is available for Linux, macOS, the web, and Windows, and is published under GPL-3.0. The project describes itself as incomplete: important features are missing, and some conglomerate cartridge hardware configurations are not emulated. Its basic command-line debugger lacks many features, and performance was not a design focus. Occasional nightly builds are distributed as prereleases.