emulator: "X Millennium"
type: libretro
core_classification: community_fork
source: "https://github.com/libretro/xmil-libretro"
upstream: "http://amethyst.yui.ne.jp/svn/x1/xmil/trunk/"
profiled_date: "2026-03-25"
core_version: "0.60a"
display_name: "Sharp X1 (X Millennium)"
cores:
  - x1
systems:
  - sharp-x1

# X Millennium (XMIL) is a Sharp X1 series emulator by yui, ported to libretro
# by r-type. Supports X1, X1 Turbo, and X1 TurboZ models via the "X1_ROMTYPE"
# core option (X1 = ROM_TYPE 1, TURBO = 2, TURBOZ = 3).
#
# SUPPORT_TURBOZ is not compiled in the libretro build (compiler.h), so TurboZ
# extended color modes are unavailable. ROM_TYPE 3 still selects IPLROM.X1T.
#
# All system files go under: <system_dir>/xmil/
# retro_init() builds: retro_system_conf = "<system_dir>/xmil" (libretro.c:597)
#
# IPL ROM loading (memio.c:87-121):
#   biosmem is initialized with defaultiplrom (575-byte boot stub from defipl.res).
#   ROM_TYPE >= 1: loads external IPL ROM into biosmem, overwriting the stub.
#   ROM_TYPE 1 (X1): xmil/IPLROM.X1
#   ROM_TYPE >= 2 (Turbo/TurboZ): xmil/IPLROM.X1T
#   Path built explicitly: sprintf(rtmp, "%s%c%s", retro_system_conf, slash, iplfile)
#   If file missing, the 575-byte stub remains (limited boot capability).
#
# Font loading (fontx1.c:69-122, font.c:89-127):
#   font_load(NULL, TRUE) called from pccore_initialize() (pccore.c:67).
#   Built-in defaults (defrom_ank, defrom_txt from fontdata.c) provide basic ASCII.
#   x1fontread() tries to load external font files via fontopen().
#   Font path resolution uses file_getcd() which defaults to "./" in the libretro
#   port (file_setcd() is never called). Upstream win9x/sdl2 calls file_setcd()
#   to set the working dir. Fonts may not be found from xmil/ in practice.
#
# .info declares firmware_count=2 (IPL ROMs only). Font files are not declared.
# .info firmware1_desc incorrectly says "8x8 Font ROM" (actually Turbo IPL ROM).

notes: |
  Place all files in: <system_dir>/xmil/
  The core selects between IPLROM.X1 and IPLROM.X1T based on the "X1_ROMTYPE"
  core option. A 575-byte built-in IPL stub provides limited boot without the
  real ROMs. Font files add Japanese character support; the libretro port has a
  path resolution quirk where fonts are searched in "./" instead of "xmil/"
  (missing file_setcd call).

files:
  - name: IPLROM.X1
    path: xmil/IPLROM.X1
    size: 32768
    required: false
    hle_fallback: true
    description: "X1 IPL ROM. Loaded when ROM_TYPE=1 (X1 model)."
    source_ref: "io/memio.c:82,96-108"

  - name: IPLROM.X1T
    path: xmil/IPLROM.X1T
    size: 32768
    required: false
    hle_fallback: true
    description: "X1 Turbo/TurboZ IPL ROM. Loaded when ROM_TYPE=2 or 3."
    source_ref: "io/memio.c:83,97-108"

  - name: FNT0808.X1
    path: xmil/FNT0808.X1
    size: 2048
    validation: [size]
    required: false
    hle_fallback: true
    description: "8x8 ANK font ROM. Built-in defrom_ank fallback provides basic ASCII."
    source_ref: "font/fontdata.c:6, font/fontx1.c:79-87"

  - name: FNT0816.X1
    path: xmil/FNT0816.X1
    size: 4096
    validation: [size]
    required: false
    hle_fallback: true
    description: "8x16 ANK font ROM. Built-in fallback derived from defrom_ank/defrom_txt."
    source_ref: "font/fontdata.c:7, font/fontx1.c:89-103"

  - name: FNT1616.X1
    path: xmil/FNT1616.X1
    size: 306176
    validation: [size]
    required: false
    description: "16x16 Kanji font ROM. No built-in kanji data (zeroed). Required for Japanese text."
    source_ref: "font/fontdata.c:8, font/fontx1.c:105-120"