emulator: "P/EMU/SDL"
type: standalone
core_classification: community_fork
source: "https://github.com/yonkuma/piemu"
upstream: "https://github.com/autch/piemu"
profiled_date: "2026-10-22"
source_commit: "0785214f13746bdfd709b1909f007e213b470ba1"
upstream_commit: "23208626e16e53b73fd21a2fbd0c429338625dc4"
core_version: "git"
display_name: "Aquaplus - P/ECE (P/EMU/SDL)"
cores:
  - "piemu"
systems:
  - aquaplus-piece

notes: |
  Autch's SDL port of Naoyuki Sawa's P/EMU, with two commits by YonKuma
  that add game controller input and a quit hotkey. AmberELEC builds this
  revision and installs piemu with the mkpfi and pfar tools built from the
  same tree.
  ref: AmberELEC packages/games/emulators/piemu/package.mk:5-6,19-29

  The emulator reads one file, piece.pfi, from its working directory: a PFI
  header with the SYSTEMINFO block, then the flash contents at the stored
  offset. A missing file, a signature other than PFI1 or a SYSTEMINFO of the
  wrong size stops it.
  ref: piemu.c:5-20, piemu.c:25-45

  That image holds the P/ECE kernel, its file system and the installed
  programs. AmberELEC's piemu.sh builds it for every launch in /tmp/piemu:
  mkpfi writes a fresh image from the kernel update image all.bin in the BIOS
  directory, then pfar adds the .pex program, its .sav file or the files a
  .pfs list names. A .pfi game never starts: the extension test lacks its `$`,
  so the image is not copied into the working directory.
  ref: AmberELEC packages/games/emulators/piemu/bin/piemu.sh:10,22-54

files:
  - name: "all.bin"
    path: "all.bin"
    system: aquaplus-piece
    required: true
    size: 516096
    description: "P/ECE kernel update image (PieceSystem 1.20, update/all.bin)"
    note: "mkpfi checks the \"Piece Kernel Program\" signature at offset 8, writes the boot vector 0x00C02004 into sector 0, leaves sector 1 blank and copies the file from sector 2. Called without -2mb, it builds the 512 KB flash layout of factory units."
    source_ref: "source tools/mkpfi.c:13, source tools/mkpfi.c:30-62, source tools/mkpfi.c:64-128"