01. Introduction to Flycast
Flycast is the gold-standard emulator for Sega's 6th-generation arcade and console hardware. It is an open-source, multi-platform emulator that accurately recreates the Sega Dreamcast console alongside a family of professional arcade boards that powered some of the most iconic titles in arcade history. If you have ever wanted to play Crazy Taxi, Marvel vs. Capcom 2, Virtua Fighter 4, or House of the Dead 2 on your arcade cabinet exactly as they were meant to be experienced, Flycast is your answer.
What makes Flycast exceptional for arcade cabinet builders is its scope. Unlike most emulators that target a single platform, Flycast covers the entire Sega 6th-generation ecosystem: the Dreamcast home console, the NAOMI arcade board (and its successor NAOMI 2), the Sammy Atomiswave, and the Sega System SP. This means a single emulator handles hundreds of arcade titles that would otherwise require multiple separate setups.
Flycast is actively maintained, receives regular updates, and supports modern features like Vulkan rendering, HD texture packs, widescreen cheats, light gun input, and even restored online multiplayer through DCnet. For arcade cabinet builders, it is one of the most rewarding emulators to configure correctly — and this guide will take you through every step.
If You Only Remember One Thing
Flycast covers five distinct hardware platforms in one emulator. Always match your BIOS files to the platform you are running — Dreamcast, NAOMI, NAOMI 2, Atomiswave, and System SP each require their own BIOS files for full compatibility.
02. Supported Hardware Platforms
Understanding what Flycast emulates is essential for building the right game library and configuring the right settings. Each platform has distinct hardware characteristics that affect how you set up ROMs, BIOS files, and performance options.
Sega Dreamcast
1998–2001The home console that launched Sega's online gaming era. Runs GDI and CHD disc images. Home to Sonic Adventure, Shenmue, Jet Grind Radio, and the definitive version of many fighting games.
Best for: Living room classics brought to the arcade
Sega NAOMI
1998–2006The arcade board that shared its architecture with the Dreamcast. Powered Crazy Taxi, House of the Dead 2, Marvel vs. Capcom 2, and Virtua Tennis. Uses .zip ROM archives.
Best for: Pure arcade cabinet authenticity
Sega NAOMI 2
2000–2005The successor to NAOMI with two CPUs and two GPUs for dramatically improved 3D performance. Runs Virtua Fighter 4, Virtua Fighter 4 Evolution, and Guilty Gear XX. Requires Vulkan or OpenGL — DirectX will crash.
Best for: The most demanding 3D arcade titles
Sammy Atomiswave
2003–2007Sammy's arcade platform built on Dreamcast hardware. Home to Guilty Gear Isuka, King of Fighters XI, Metal Slug 6, and Fist of the North Star. Uses .zip ROM archives with awbios.zip.
Best for: Fighting game collections
Sega System SP
2004–2008A compact arcade platform designed for redemption and card-based games. Famous for Mushiking and Dinosaur King, which used physical barcode trading cards. Flycast emulates the card scanner.
Best for: Novelty and collector arcade experiences
NAOMI 2 Critical Warning
NAOMI 2 games (Virtua Fighter 4, Virtua Fighter 4 Evolution) will crash or boot loop if you use DirectX 9 or DirectX 11 as your graphics API. This is a known hardware limitation — NAOMI 2's dual-GPU architecture is incompatible with DirectX rendering in Flycast. Always use Vulkan or OpenGL for NAOMI 2 titles.
03. ROM Formats & Game Files
Flycast supports multiple file formats depending on which platform you are running. Choosing the right format saves storage space, ensures compatibility, and prevents audio or video quality loss. Here is a plain-English breakdown of every format you will encounter.
The best format for Dreamcast games. CHD (Compressed Hunks of Data) takes a perfect copy of the original disc and compresses it into a single file with zero quality loss. Smaller than GDI, easier to manage, and fully accurate. Always choose CHD when available.
A perfect, raw dump of the original GD-ROM disc. Fully accurate but consists of multiple files (a .gdi index plus multiple .bin/.raw tracks) that must be kept together in the same folder. Takes significantly more storage than CHD.
Originally created to fit Dreamcast games onto blank CD-Rs. These are not accurate dumps — they often have cut content, compressed audio, or lower-quality video to save space. Only use CDI if no GDI or CHD version exists.
NAOMI, NAOMI 2, Atomiswave, and System SP games use compressed .zip archives — exactly like MAME. Do not extract these. Flycast reads them directly from the zip, just as the original arcade hardware would read from its ROM chips.
If You Only Remember One Thing
For Dreamcast: always use CHD. For arcade boards (NAOMI, Atomiswave): always leave ROMs in their .zip archives. Never extract arcade zips.
04. BIOS Setup
Flycast includes a built-in "HLE" (High-Level Emulation) BIOS that can boot many games without real firmware files. However, for maximum compatibility — especially with arcade hardware — you need the original BIOS files. Missing or incorrect BIOS files are the number-one cause of games failing to boot.
BIOS File Placement
Where you place BIOS files depends on whether you are using standalone Flycast or Flycast through RetroArch:
Standalone Flycast
flycast/data/Place all BIOS files directly in the data folder inside your Flycast installation directory.
RetroArch (Flycast Core)
RetroArch/system/dc/Place all BIOS files in the system/dc subfolder of your RetroArch installation.
Required BIOS Files by Platform
| Platform | File Name | Purpose |
|---|---|---|
| Dreamcast | dc_boot.bin | System menu and boot ROM — the console's main firmware |
| Dreamcast | dc_flash.bin | Stores time, date, language, and regional settings |
| NAOMI 1 | naomi.zip | NAOMI arcade board firmware — required for all NAOMI 1 games |
| NAOMI 2 | naomi2.zip | NAOMI 2 arcade board firmware — required for VF4 and other NAOMI 2 titles |
| Atomiswave | awbios.zip | Sammy Atomiswave board firmware — required for all Atomiswave games |
BIOS Sourcing Note
BIOS files are copyrighted firmware owned by Sega. They must be dumped from hardware you legally own. G&G Arcade does not distribute BIOS files. Every G&G Arcade cabinet ships with all necessary BIOS files pre-loaded and pre-configured — no hunting required.
05. Installation & First Launch
Flycast is available as a standalone application and as a RetroArch core. For arcade cabinet use, standalone Flycast gives you the most direct control over settings and is the recommended approach for dedicated cabinet builds.
Standalone Installation Steps
Download Flycast
Get the latest release from the official GitHub repository at github.com/flyinghead/flycast. Download the Windows x64 build (.zip).
Extract to a Permanent Location
Extract the zip to a stable folder such as C:\Emulators\Flycast\. Avoid the Downloads folder or Desktop — these locations can cause permission issues.
Create the Data Folder
Inside the Flycast folder, create a subfolder named data. This is where all BIOS files will live.
Place BIOS Files
Copy dc_boot.bin, dc_flash.bin, naomi.zip, naomi2.zip, and awbios.zip into the data folder. Flycast will auto-detect them on first launch.
Launch and Set ROM Path
Run flycast.exe. Go to Settings → General and set your Content Path to the folder containing your game files. Flycast will scan and build a game library automatically.
Verify BIOS Detection
Go to Settings → About. If your BIOS files are detected correctly, you will see green checkmarks next to each platform. Red X marks indicate missing or misnamed files.
Video Tutorial: Complete Flycast Setup Guide
A thorough walkthrough covering installation, BIOS setup, and first launch for Dreamcast, NAOMI, and Atomiswave.
06. Graphics & Performance
Flycast's graphics settings have a dramatic impact on both visual quality and performance. Understanding the three core settings — Graphics API, Alpha Sorting, and Widescreen — will let you dial in a perfect image for any game.
Choosing Your Graphics API
Best option for modern hardware. Highest performance, lowest input delay, and full NAOMI 2 compatibility. Use this as your default.
Excellent stability on Windows. Fully compatible with NAOMI 2. Use this if you experience Vulkan driver issues on older GPUs.
Works for Dreamcast and NAOMI 1, but will crash or boot loop on NAOMI 2 games. Not recommended for mixed-platform cabinets.
Alpha Sorting: Fixing Transparency
Sega arcade boards used complex methods to render transparent objects — glass, water, fog, character effects. Flycast gives you three modes to handle this, each with a different performance vs. accuracy tradeoff:
Per-Strip
Perf: Fastest
Accuracy: Low
Designed for weak devices. Causes visible graphical glitches — "holes" in character models, incorrect transparency on water and glass. Avoid on modern hardware.
Per-Triangle
Perf: Balanced
Accuracy: Medium
The default setting. Balances speed and accuracy well for most games. A good starting point for any title.
Per-Pixel
Perf: Demanding
Accuracy: Highest
The most accurate method. Perfectly fixes all transparency bugs at the cost of GPU load. Use this on modern hardware for the best visual experience.
Widescreen: The Right Way
Every modern arcade cabinet runs a 16:9 display, but Dreamcast and NAOMI games were built for 4:3 CRT TVs. There are two ways to fill your screen — one is broken, and one is correct:
❌ Widescreen Hack (Avoid)
Forces the emulator to draw outside the original 4:3 frame, but the game engine does not know this is happening. Objects pop in and disappear at screen edges because the game's culling system still thinks it is rendering a 4:3 image.
✅ Widescreen Cheats (Recommended)
Memory patches that modify the game's rendering code to natively output widescreen. The game engine knows it is in widescreen mode, so no pop-in occurs. Enable "Widescreen Cheats" and set Horizontal Stretching to 133% for a perfect 16:9 image.
Video Tutorial: Best Settings & Graphics Optimization
Deep dive into Flycast's graphics settings, alpha sorting, and performance tuning for modern hardware.
If You Only Remember One Thing
Use Vulkan + Per-Pixel alpha sorting + Widescreen Cheats at 133% horizontal stretch. This combination gives you the most accurate, visually stunning image on any modern arcade cabinet display.
07. Controller Configuration
The Dreamcast controller had a unique design with two expansion slots per controller — one for a memory card (VMU) and one for accessories like the rumble pack. Flycast faithfully emulates this slot system, which means a few configuration quirks to be aware of.
Rumble Pack Slot Mapping
The Slot 2 Trick
On the original Dreamcast hardware, the vibration pack (Purupuru Pack) was typically placed in the second slot of the controller, not the first. Many games check specifically for rumble in Slot 2. When mapping your controller in Flycast, assign rumble/vibration to Slot 2 to ensure maximum game compatibility. Games that do not detect rumble in Slot 1 will work correctly with this configuration.
Per-Game VMU (Memory Cards)
The original Dreamcast VMU only held 200 blocks of save data — enough for a handful of games before it fills up. Flycast solves this elegantly with the Per-Game VMU feature:
Enable Per-Game VMU A1
Go to Settings → Controls and enable Per-Game VMU A1. This creates a separate, dedicated VMU file for every single game you boot. You will never run out of save space, and saves from different games will never conflict with each other. This is the recommended setting for all arcade cabinet builds.
Light Gun Setup (House of the Dead, Confidential Mission)
Flycast has excellent light gun support for arcade shooters. Whether you are using a Sinden Light Gun, a mouse, or any other pointing device, the setup process is straightforward:
Go to Settings → Controls and set the input device for Port A to Light Gun.
Enable Use Raw Input. This is mandatory for 2-player light gun games — it allows Flycast to distinguish between two separate mice or guns connected to the same PC.
Map your Reload button to the Trigger Offscreen command. Alternatively, many games support flicking the cursor to the edge of the screen to auto-reload — test your specific game to see which method works.
For Sinden Light Gun users: enable the Sinden border overlay in the Sinden software before launching Flycast. The border is required for the Sinden's camera-based tracking to function.
08. Advanced Configurations
Some games require specific settings to run correctly, and Flycast has several advanced features that unlock unique capabilities. This section covers the configurations that separate a basic setup from a truly polished arcade experience.
Windows CE Games
Approximately 25% of Dreamcast games were built using the Windows CE operating system — including Sega Rally 2, Resident Evil 2, and several sports titles. These games are significantly more demanding to emulate because they require full emulation of the console's Memory Management Unit (MMU).
- → Enable Force Windows CE Mode in Settings for these titles.
- → For Sega Rally 2 specifically: also disable DIV matching, or the game will hang and crash during startup.
- → Windows CE games may run slower than non-CE titles on the same hardware. This is expected behavior due to the increased emulation complexity.
HD Texture Packs
The Flycast community has created stunning 4K texture packs for popular titles like Sonic Adventure, Marvel vs. Capcom 2, and Crazy Taxi. Installing them is straightforward:
Inside your Flycast data folder, create a new folder called TEXTURES (all caps — this is required).
Place your downloaded texture pack inside the TEXTURES folder. Each game's textures go in a subfolder named after the game's serial number.
In Settings → Video, enable Load Custom Textures.
Also enable Preload Custom Textures. This loads all textures into RAM when the game boots, preventing stuttering when entering new areas.
DCnet: Restored Online Multiplayer
The Dreamcast was a pioneer in console online gaming, and Flycast has brought it back through DCnet — a free, built-in VPN that connects to revived community servers with zero router configuration required.
- → Go to Settings → Network and check Use DCnet.
- → Critical Rule: When a game asks you to register an account (NFL 2K2, Pod Racer, etc.), your username and password must be exactly 6 characters long. Anything else will fail silently. Use the same credentials every time to track global high scores.
- → Supported games include NFL 2K2, NBA 2K2, Quake III Arena, Alien Front Online, and many others.
Microphone Games (Seaman)
Seaman — the legendary game where you raise and converse with a fish-man hybrid — required a microphone peripheral. Flycast supports this through your PC's built-in or external microphone:
Go to Controls → Port A. Set the first slot to Sega VMU and the second slot to Microphone. Flycast will route your PC microphone directly into the game.
System SP: RFID Card Scanning
Arcade games like Mushiking and Dinosaur King required players to physically swipe barcode trading cards at the cabinet. Flycast emulates this scanner completely:
When the arcade game prompts for a card, open the Flycast quick menu, manually type the barcode number of the card you want, and press your mapped Insert Card button. Full card databases are available from the community.
Video Tutorial: NAOMI Arcade Setup Deep Dive
Covers NAOMI 1 and 2 ROM setup, BIOS configuration, and arcade-specific settings for cabinet use.
If You Only Remember One Thing
Enable Per-Game VMU A1 for unlimited save space, use Widescreen Cheats (not the Widescreen Hack) for clean 16:9 output, and always use Vulkan for NAOMI 2 titles. These three settings alone eliminate 90% of common Flycast problems.
09. Arcade Automation & Kiosk Mode
For arcade cabinet use, Flycast needs to behave like a dedicated appliance — launching games automatically, hiding desktop elements, and returning to the game library when a session ends. The following configurations transform Flycast from a desktop application into a true arcade experience.
LaunchBox / BigBox Integration
LaunchBox is the recommended frontend for managing Flycast on an arcade cabinet. It handles game launching, artwork display, and controller navigation without requiring a keyboard or mouse.
Add Flycast as an Emulator
In LaunchBox, go to Tools → Manage Emulators → Add. Set the emulator path to flycast.exe. Use the command-line parameter %romfile% to pass the game path.
Separate Platforms
Create separate LaunchBox platforms for Dreamcast, NAOMI, and Atomiswave. This allows per-platform artwork, metadata, and settings.
Full-Screen Launch
In Flycast settings, enable Full Screen on Launch. Combined with LaunchBox's BigBox mode, games launch directly into full-screen without any desktop visible.
Exit Button Mapping
Map a controller button combination (e.g., Start + Select held for 3 seconds) to the Flycast exit command. This returns players to BigBox without needing a keyboard.
Attract Mode Configuration
For cabinets in public or semi-public spaces, attract mode keeps the screen active and draws attention when no one is playing. Configure BigBox to cycle through game trailers and screenshots automatically after a set idle period.
- → In BigBox Options → Attract Mode, set the idle timeout to 3–5 minutes.
- → Enable video snaps for Dreamcast and NAOMI games — LaunchBox's community database has trailers for virtually every title.
- → Set attract mode to shuffle through your entire Flycast library for maximum visual variety.
If You Only Remember One Thing
Enable Full Screen on Launch in Flycast and map a controller exit combo. These two settings are the foundation of a seamless arcade cabinet experience — no keyboard needed, no desktop visible.
10. Top Dreamcast & NAOMI Games for Arcade Cabinets
The Sega Dreamcast and NAOMI library contains some of the most iconic arcade titles ever made. These are the games that draw crowds, generate repeat plays, and define what a great arcade cabinet experience feels like.
| Game | Platform | Genre | Cabinet Notes |
|---|---|---|---|
| Crazy Taxi | NAOMI / DC | Arcade Racing | Iconic soundtrack, simple controls, endlessly replayable. Perfect crowd-pleaser. |
| Marvel vs. Capcom 2 | NAOMI / DC | Fighting | The definitive version. 56-character roster. Requires Per-Pixel alpha for clean visuals. |
| House of the Dead 2 | NAOMI / DC | Light Gun Shooter | Requires light gun setup. 2-player co-op is a cabinet highlight. |
| Virtua Fighter 4 Evolution | NAOMI 2 | Fighting | NAOMI 2 only — use Vulkan. The most technically impressive fighter of its era. |
| Guilty Gear XX #Reload | Atomiswave | Fighting | Stunning hand-drawn sprites. Atomiswave version is arcade-authentic. |
| Virtua Tennis | NAOMI | Sports | Accessible, fun for all ages. 4-player doubles mode is a cabinet party game. |
| Sega Rally 2 | NAOMI / DC | Racing | Enable Windows CE Mode + disable DIV matching for stable performance. |
| Jet Grind Radio | Dreamcast | Action | Cel-shaded visuals hold up beautifully. Widescreen cheats work perfectly. |
| Sonic Adventure 2 | Dreamcast | Platformer | HD texture packs available. Widescreen cheats supported. |
| Confidential Mission | NAOMI | Light Gun Shooter | Excellent 2-player co-op. Pairs perfectly with House of the Dead 2. |
| Metal Slug 6 | Atomiswave | Run & Gun | The only console-quality Metal Slug on Atomiswave. Stunning sprite work. |
| King of Fighters XI | Atomiswave | Fighting | Excellent roster, smooth gameplay. Great complement to Marvel vs. Capcom 2. |
| Ikaruga | NAOMI | Shoot 'em Up | One of the greatest shmups ever made. Vertical orientation recommended. |
| Power Stone 2 | Dreamcast | Arena Fighter | 4-player chaos. One of the best multiplayer games in the Dreamcast library. |
| Shenmue | Dreamcast | Adventure | A landmark title. Best experienced as a showcase piece on a premium cabinet. |
Video: Flycast 2025 — Dreamcast, NAOMI & Atomiswave Showcase
See the full range of Flycast-supported hardware in action, including NAOMI and Atomiswave arcade titles.
11. Troubleshooting
Most Flycast issues have straightforward solutions. Here are the most common problems and their fixes, organized by symptom.
Problem: Game is stuck in a loop asking for the Date and Time
Cause: Corrupted save data or incorrect BIOS flash file
Fix: Delete any .nvmem files or vmu_save.bin files in your Flycast data directory. Verify that your dc_flash.bin BIOS file is the correct version for your region. The flash file stores the console's clock and language settings — a corrupted or wrong-region flash causes this loop.
Problem: NAOMI 2 games are lagging and stuttering
Cause: NAOMI 2 used two CPUs and two GPUs — it is the most demanding platform Flycast emulates
Fix: Drop internal resolution to native (640x480), change Alpha Sorting to Per-Strip, and confirm you are using Vulkan. If you are using save states during testing, disable Multi-threaded emulation — it can cause crashes when combined with save states.
Problem: NAOMI 2 game crashes or boot loops immediately
Cause: Using DirectX as the graphics API
Fix: Switch your Graphics API to Vulkan or OpenGL. DirectX 9 and DirectX 11 do not support NAOMI 2's dual-GPU architecture and will cause immediate crashes.
Problem: Windows CE game hangs or crashes at startup
Cause: Windows CE mode not enabled, or DIV matching issue (Sega Rally 2)
Fix: Enable Force Windows CE Mode in Settings. For Sega Rally 2 specifically, also disable DIV matching. These settings are required for all Windows CE-based Dreamcast games.
Problem: Light gun not working or only one gun recognized in 2-player mode
Cause: Raw Input not enabled
Fix: Go to Settings → Controls and enable Use Raw Input. This is mandatory for multi-gun setups — without it, the system cannot distinguish between two separate pointing devices.
Problem: Objects popping in at screen edges in widescreen mode
Cause: Using the Widescreen Hack instead of Widescreen Cheats
Fix: Disable the Widescreen Hack. Instead, enable Widescreen Cheats and set Horizontal Stretching to 133%. The cheats modify the game's rendering code so the engine knows it is in widescreen mode, eliminating pop-in.
Problem: Rumble/vibration not working in some games
Cause: Rumble mapped to controller Slot 1 instead of Slot 2
Fix: In controller mapping, move your rumble/vibration assignment to Slot 2. The original Dreamcast hardware placed the vibration pack in the second expansion slot, and many games check specifically for it there.
Problem: Game stutters when entering new areas with HD textures
Cause: Custom textures loading on-demand instead of preloading
Fix: In Settings → Video, enable Preload Custom Textures. This loads all texture data into RAM when the game boots, preventing mid-game stuttering at the cost of a longer initial load time.
12. Legal & Compliance
Flycast itself is 100% legal. It is an open-source emulator released under the GNU General Public License v2. Downloading, using, and distributing Flycast is entirely lawful.
BIOS files are copyrighted firmware. The dc_boot.bin, dc_flash.bin, naomi.zip, naomi2.zip, and awbios.zip files are proprietary Sega firmware. They must be dumped from hardware you legally own. Distributing or downloading these files from the internet without owning the original hardware is a copyright infringement.
Game ROMs and disc images are copyrighted software. Dreamcast GDI/CHD files and arcade ROM zips are protected by copyright. The legality of possessing ROM files varies by jurisdiction. Many legal scholars argue that backup copies of software you own are permissible under fair use, but this has not been definitively established in court. G&G Arcade does not distribute game files.
Commercial use requires licensing. Operating a public arcade cabinet with copyrighted games for commercial purposes (charging per-play, operating in a business open to the public) requires proper licensing from the rights holders. This applies regardless of whether you are using original hardware or emulation.
This section is provided for informational purposes only and does not constitute legal advice. Consult a qualified attorney for guidance specific to your situation and jurisdiction.
Ready to Skip the Setup?
Every G&G Arcade cabinet ships with Flycast pre-configured, all BIOS files loaded, Vulkan optimized, widescreen cheats enabled, and your favorite Dreamcast and NAOMI titles ready to play. No BIOS hunting. No settings tweaking. Just plug in and play.