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# vecx - RetroBIOS

Type | libretro
Classification | community_fork
Source | https://github.com/libretro/libretro-vecx
Upstream | https://github.com/jhawthorn/vecx
Version | SVN
Profiled | 2026-03-25
Cores | vecx
Systems | gce-vectrex

Platform details

bios_mapping: - target: 0xE000-0xFFFF in Vectrex address space (8 KB) - source_ref: vecx.c:40 (unsigned char rom[8192]), vecx.c:437-439 (read handler) - notes: CPU reads from 0xE000-0xFFFF are served from rom[] via

address & 0x1FFF masking. The array is populated from the compiled-in bios_data at retro_load_game() time.

    **embedded_bios:**
    - source_ref: libretro.c:20-30, bios/system.h
    - standard_bios: {'md5': 'ab082fa8c8e632dd68589a8c7741388f', 'sha1': '65d07426b520ddd3115d40f255511e0fd2e20ae7', 'size': 8192}
    - fast_bios: {'md5': 'a970aed37cffd29ab3740f8e79518858', 'sha1': 'e0900be6d6858b985fd7f0999d864b2fceaf01a1', 'size': 8192}
    - skip_bios: {'md5': '05f32c2b18b6fb168ab976989e86dfb1', 'sha1': '6c891bd74acb201d54071b310bd6df6617cdf205', 'size': 8192}
    - notes: All three variants are 8192 bytes, compiled as C arrays in

bios/*.h headers. STANDARD_BIOS is the authentic Vectrex ROM. FAST_BIOS and skip are modified versions for faster startup. Selection is compile-time only (#ifdef chain, libretro.c:20-30).

Technical notes

vecx is a GCE Vectrex emulator ported to libretro.

The Vectrex system ROM (8192 bytes) is fully embedded in the binary. There are three compile-time BIOS variants in bios/: - system.h (STANDARD_BIOS, default) - original Vectrex ROM - fast.h (FAST_BIOS) - modified BIOS with faster boot - skip.h - modified BIOS that skips the intro

The default build uses STANDARD_BIOS via #define at libretro.c:20. At load time (retro_load_game, libretro.c:736): memcpy(rom, bios_data, bios_data_size); This copies the compiled-in BIOS data into the rom[8192] array (vecx.c:40, mapped at 0xE000-0xFFFF via vecx.c:437-439).

The core never calls RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY and has no code path to load an external BIOS file from disk. No .info file is shipped with the repo declaring firmware requirements.

rom.dat in the repo root is identical to bios/system.bin (same MD5: ab082fa8c8e632dd68589a8c7741388f), likely kept for standalone builds.

No BIOS or firmware files required. Generated on 2026-03-25T14:56:43Z