---
title: "melonDS: BIOS missing — set up NDS BIOS or use built-in HLE firmware"
canonical_url: https://emudesk.com/issues/melon-ds-bios-missing-nds-setup
content_locale: en
source_locale: en
entity_type: issue
index_status: index
published_at: 2026-08-31T18:22:23.000Z
updated_at: 2026-09-01T00:45:02.747Z
freshness_status: fresh
---

# melonDS: BIOS missing — set up NDS BIOS or use built-in HLE firmware

melonDS requires either real Nintendo DS BIOS files (dumped from hardware you own) or its built-in HLE firmware to boot DS games. Until you choose one of these two paths and configure it, every game will fail to start.

You pointed melonDS at a DS ROM and ran into one of these:


  "BIOS not found" or a similar error on launch
  melonDS opens but the game screen stays black or immediately returns to the emulator
  The configuration screen asks for bios7.bin, bios9.bin, and firmware.bin but you don't know where to get them
  DSi mode fails even though regular DS games work
  Some games boot on HLE but crash at a specific screen where real BIOS games don't


Two valid paths — choose one:

  HLE firmware (built-in, no BIOS files needed): melonDS includes a high-level emulation (HLE) substitute for the DS firmware. It works for the vast majority of commercial DS games and does not require any files from hardware. This is the easiest starting point.
  Real BIOS + firmware (most accurate): Three files dumped from a Nintendo DS or DS Lite you own: bios7.bin (ARM7 BIOS, 16 384 bytes), bios9.bin (ARM9 BIOS, 4 096 bytes), and firmware.bin (~131 072 or ~262 144 bytes depending on console). Required for DSi mode and for the small subset of games that call directly into BIOS routines the HLE doesn't cover.


The legal line: NDS BIOS and firmware files are copyrighted by Nintendo. The only legal path is to dump them from a Nintendo DS or DS Lite you own using a dumping tool. EmuDesk does not host, link to, or endorse any site distributing pre-dumped BIOS files.

Re-test after completing each step below.