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RetroBIOS

NP2kai

NP2kai emulates NEC PC-98. It reads 21 files, none of them required: it starts games without them.

About this profile
Detail Value
Type libretro
Classification Enhanced fork
Source https://github.com/libretro/NP2kai
Upstream https://github.com/AZO234/NP2kai
Version 0.86, stated in np2ver.h
Revision libretro/NP2kai@1ea561cd7fd6, AZO234/NP2kai@5d47f3a04b0b
Profiled 2026-03-24
Profile YAML, JSON
Cores np2kai
Systems NEC PC-98
Install this emulator's files

The installer finds your setup and its BIOS folder, then downloads only the files this emulator reads there and checks each one.

Open the Start menu. Type PowerShell and open it. Paste the line. Press Enter.

PowerShell
&([scriptblock]::Create((irm https://abdess.github.io/retrobios/i.ps1))) --emulator np2kai

Files

Section titled “Files”

21 files: 0 required, 21 optional. 8 have an HLE fallback.

In this collection: 19 in repo, 0 missing and 2 unsourceable.

Optional

Section titled “Optional”
21 rows
FileStatus

bios.rom

  • Path: np2kai/bios.rom
  • PC-9801 system BIOS ROM. The first 0x18000 bytes are read to 0xe8000. A file shorter than that is ignored and the built-in BIOS simulator is used, as when the file is absent.
Validation and source
in repo HLE fallback

font.bmp

  • Path: np2kai/font.bmp
  • Aliases: FONT.ROM, font.rom, FONT.BMP
  • PC-98 font bitmap. Required for correct Japanese kanji display. Without this, only basic ASCII renders using built-in 8x8 data. FONT.ROM (V98 format) is also accepted.
Source
in repo HLE fallback

sound.rom

  • Path: np2kai/sound.rom
  • FM sound board BIOS ROM (16 KB). Generic fallback for all sound boards. Board-specific variants are tried first: sound26.rom (PC-9801-26K), sound86.rom (86), sound118.rom (118), soundSPB.rom (Speak Board), soundMO.rom (MO), sound14.rom (14).
Source
in repo HLE fallback

2608_bd.wav

  • Path: np2kai/2608_bd.wav
  • YM2608 OPNA rhythm sample: bass drum
Source
in repo

2608_sd.wav

  • Path: np2kai/2608_sd.wav
  • YM2608 OPNA rhythm sample: snare drum
Source
in repo

2608_top.wav

  • Path: np2kai/2608_top.wav
  • YM2608 OPNA rhythm sample: top cymbal
Source
in repo

2608_hh.wav

  • Path: np2kai/2608_hh.wav
  • YM2608 OPNA rhythm sample: hi-hat
Source
in repo

2608_tom.wav

  • Path: np2kai/2608_tom.wav
  • YM2608 OPNA rhythm sample: tom
Source
in repo

2608_rim.wav

  • Path: np2kai/2608_rim.wav
  • YM2608 OPNA rhythm sample: rim shot
Source
in repo

2608_BD.WAV

  • Path: np2kai/2608_BD.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: bass drum
Source
in repo

2608_SD.WAV

  • Path: np2kai/2608_SD.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: snare drum
Source
in repo

2608_TOP.WAV

  • Path: np2kai/2608_TOP.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: top cymbal
Source
in repo

2608_HH.WAV

  • Path: np2kai/2608_HH.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: hi-hat
Source
in repo

2608_TOM.WAV

  • Path: np2kai/2608_TOM.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: tom
Source
in repo

2608_RIM.WAV

  • Path: np2kai/2608_RIM.WAV
  • YM2608 OPNA rhythm sample for the fmgen engine: rim shot. When it is missing fmgen tries 2608_RYM.WAV, but strncpy drops the directory, so that name is opened from the working directory, not from np2kai/.
Source
in repo

ide.rom

  • Path: np2kai/ide.rom
  • Aliases: d8000.rom, bank3.bin, bios9821.rom
  • IDE BIOS of a PC-9821, the ROM a real machine maps at D8000h. The first 0x2000 bytes of the first name found are read to idebaddr << 12 and nothing past them. A shorter file is dropped. Without a loaded ROM the emulated IDE BIOS is used.
Validation and source
in repo HLE fallback

scsi.rom

  • Path: np2kai/scsi.rom
  • SCSI controller BIOS ROM, up to 16 KB: the full-size test is commented out and a shorter file is used as read. The core includes a built-in SCSI BIOS stub as fallback.
Source
in repo HLE fallback

sasi.rom

  • Path: np2kai/sasi.rom
  • SASI controller BIOS ROM (4 KB). The core includes a built-in SASI BIOS stub as fallback.
Source
  • Asked for by: emulator code, libretro port
  • Source: cbus/sasiio.c:451-467 (emulator code, libretro port)
in repo HLE fallback

pci.rom

  • Path: np2kai/pci.rom
  • Aliases: bank0.bin
  • PCI BIOS ROM (32 KB). For PC-9821 PCI bus emulation. Without this, the built-in PCI BIOS simulator is used.
Source
  • Asked for by: emulator code, libretro port
  • Source: io/pcidev.c:356-382 (emulator code, libretro port)
in repo HLE fallback

gpib.rom

  • Path: np2kai/gpib.rom

  • GP-IB interface BIOS ROM (8 KB). If missing, GP-IB emulation is disabled entirely.

  • Not collectable: never publicly dumped, GP-IB emulation is stub code (source comment: not implemented) (acknowledged gaps)

  • Size: 8.0 KB
Source
  • Asked for by: emulator code, libretro port
  • Source: cbus/gpibio.c:320-356 (emulator code, libretro port)
unsourceable

key.txt

  • Path: np2kai/key.txt

  • Keyboard remapping configuration (text file). User-created file for custom keyboard layout. The core uses built-in defaults if absent.

  • Not collectable: user-created keyboard config, no default distributed in any NP2kai release (acknowledged gaps)

Source
unsourceable HLE fallback

Next steps

Section titled “Next steps”
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Maintained by Abdess on GitHub. Report a problem.

Packs from release v2026.10.10, .

MIT for the tooling and metadata. BIOS and firmware files are third-party system software, preserved for personal backup, archival and interoperability.