R36S GBA Settings: How to Optimize Game Boy Advance Emulation

Best GBA Emulator Core for R36S

RetroArch offers two GBA cores on the R36S: mGBA and gpSP. Each has different strengths, and the right choice depends on what you want from your GBA experience.

mGBA — Recommended for Most Users

mGBA is the most accurate and feature-complete GBA emulator available for RetroArch. It handles virtually every GBA game correctly and includes several quality-of-life options that enhance the experience.

mGBA strengths:

• Near-perfect game compatibility — runs 99%+ of the GBA library correctly
• Excellent audio accuracy, including proper emulation of the notoriously tricky GBA audio hardware
• Support for RTC (real-time clock) in games like Pokémon Ruby/Sapphire
• Game Boy and Game Boy Color backward compatibility
• Solar sensor emulation for Boktai games
• Tilt sensor support for WarioWare: Twisted (using device accelerometer)

gpSP — For Maximum Performance

gpSP is a lightweight, speed-focused GBA emulator. It runs at lower CPU usage than mGBA, which can extend battery life by 20–30 minutes per session. However, it has lower compatibility and some audio inaccuracies.

gpSP strengths:

• Lower CPU usage = better battery life
• Very fast performance on all GBA games
• Good compatibility for the majority of the library

gpSP weaknesses:

• Some games have graphical glitches or audio issues
• No GB/GBC backward compatibility
• Limited RTC support
• Less active development than mGBA

Switching to mGBA

If your R36S firmware defaulted to gpSP, switching to mGBA takes less than a minute:

1. From the main firmware menu, navigate to your GBA game
2. Instead of launching, press the game options button (often Y or the select button)
3. Choose "Edit This Game's Metadata" or "Change Core"
4. Select "mGBA" from the list
5. Alternatively, open RetroArch directly, go to Load Core, and select mGBA, then load your game via Load Content

mGBA Core Configuration

Once mGBA is selected, access the core options while a game is running to fine-tune the experience. Press SELECT + START (or your firmware's hotkey) to open the RetroArch Quick Menu, then navigate to Core Options.

Essential Core Options

Color Correction Explained

The original Game Boy Advance had a screen with limited brightness and a slight color cast. Many GBA games were designed with this in mind — colors that look oversaturated on a modern IPS display actually look accurate when color correction is enabled.

• No color correction: Vivid, saturated colors. Looks "nice" but not authentic to original hardware
• Game Boy Advance: Authentic color reproduction matching original GBA screen characteristics
• Game Boy Advance (Simple): A less aggressive correction; good middle ground

Try both and see which you prefer. Many users find the corrected colors look more "correct" for games specifically designed for the GBA's dimmer screen.

Interframe Blending

Some GBA games use a transparency trick that alternates sprites between frames to create a transparency effect — visible on original hardware but causing flickering on emulators. The mGBA interframe blending option addresses this:

• Off: No blending. Flickering visible in games that use this technique (e.g., some effects in Castlevania: Aria of Sorrow)
• Mix frames: Always blends consecutive frames. Reduces sharpness slightly but eliminates flicker
• Smart: Only blends when the game is actively using the flicker technique. Best option for most users

Display and Shader Settings

The R36S's 640×480 screen is an excellent match for GBA content. A 240×160 GBA image scales to exactly 3x (720×480 is closest, fitting with slight letterbox). With the right settings, GBA games look sharp and clean.

Aspect Ratio and Integer Scaling

GBA has a 3:2 aspect ratio (240×160 pixels). On the R36S's 4:3 screen, you have two options:

• Integer scale (3x): 720×480 — a perfectly sharp 3x scale. Leaves small black bars on the left and right. Every GBA pixel maps to exactly 9 screen pixels. Recommended.
• Fit screen / custom aspect: Stretches to fill more of the screen but introduces non-integer scaling, causing a slight softness.

To enable integer scaling in RetroArch:

1. Open Quick Menu → Settings → Video
2. Set "Integer Scale" to ON
3. Set "Aspect Ratio" to "Core Provided" or "4:3"

Recommended Shaders for GBA

RetroArch shaders can simulate the look of original hardware screens. For GBA, these are popular choices:

• No shader (default): Sharp, clean pixels. Great for users who prefer a crisp modern look.
• LCD3x shader: Simulates GBA LCD pixel grid with soft glow between pixels. Closest to original hardware appearance.
• Sharp-bilinear: Slight softening of pixel edges while maintaining sharpness. Good middle ground.
• zfast-lcd: Lightweight LCD effect with minimal performance impact.

To apply a shader:

1. Open Quick Menu → Shaders → Load Shader Preset
2. Navigate to the shaders/presets folder
3. Select your preferred shader file (.slangp or .glslp)
4. To keep it permanently: "Save Core Preset" to apply to all GBA games, or "Save Game Preset" for just this title

Audio Settings for GBA

GBA audio emulation in mGBA is excellent by default, but a few settings can improve the experience further.

RetroArch Audio Settings

Access these from Quick Menu → Settings → Audio while a GBA game is running:

• Audio Latency: 64ms default. Reduce to 32ms for slightly more responsive feel; increase to 96ms if you experience audio crackling
• Audio Synchronization: Keep ON. This prevents audio desync over long play sessions
• Volume: GBA games can be quiet. Setting this to 150% is safe and improves audibility without distortion

GBA-Specific Audio Notes

A few GBA games have known audio quirks:

• Games using PCM/DirectSound samples (most modern GBA titles): Sound perfectly in mGBA
• Older GBA games using GB-style square wave audio: Also accurate in mGBA
• Pokémon FireRed/LeafGreen: Some users report slight audio pitch issues at certain sample rates. If this occurs, try changing the RetroArch audio output rate from 44100Hz to 48000Hz

Save States and Game-Specific Tips

Save State Hotkeys

RetroArch save states are one of the most useful features for GBA gaming. The default hotkeys on R36S are:

• Save state: SELECT + R1 (or configured hotkey)
• Load state: SELECT + L1
• Next save slot: SELECT + R2
• Previous save slot: SELECT + L2

Using multiple save slots lets you create manual checkpoints throughout a game. This is especially useful for challenging games like Mega Man Zero or difficult Pokémon battles.

GBA Games With Special Requirements