mGBA Wi-Fi Link Netplay v0.1.0-alpha.2

Historical prerelease: Superseded by GBA Wi-Fi Link v0.2.0 alpha. Kept for provenance; use v0.2.0 for current testing and documentation.

mGBA Wi-Fi Link Netplay v0.1.0-alpha.2

This experimental alpha replaces the latency-bound distributed-cable runtime from alpha.1 with the reviewed protocol-v2 replicated-pair architecture. Each Android device runs the same local P0/P1 mGBA pair; RetroArch Netpacket exchanges frame inputs and verification data rather than placing every cable word behind a Wi-Fi round trip.

The result is full-speed two-player Multi-Pak play in the validated workloads. PR #3 was independently code-reviewed and merged into master. This release binary is the exact physically exercised ARM64 artifact built from source commit c9b181aa24d5f2136a6e11fca56179b5204555be:

14978106a3978ab4ef6ec025add82e0e9a38decda72404e3dc8c02b3373f179d  mgba_libretro_android.so

Install

Download the Android ARM64 bundle, extract it, then install mgba_libretro_android.so through RetroArch → Load Core → Install or Restore a Core on both devices. Both players must load byte-identical ROM revisions with this same core.

Player one starts a Netplay host. Player two connects to the host's LAN address. Wait for the replicated-link-ready message on both devices, return to the running games, and enter the title's Multi-Pak flow.

Qualification and compatibility

• Mario Kart: Super Circuit: verified, including a complete three-lap VS race on the protocol-v2 architecture and an exact-artifact corrective smoke
• continuous diagnostic and LinkCable workloads: verified
• Advance Wars: successful ad-hoc playtest
• Zelda: Four Swords: known compatibility failure during cable discovery
• other commercial titles: unverified

The exact release artifact sustained approximately 60 FPS with matching replica checks, normal audio delivery, 6,550 Mario Kart transfers in its corrective smoke, and safe verified-checkpoint restoration after forced peer stop. Longer qualification evidence from earlier protocol-v2 candidates is retained in the repository validation matrix.

Scope and limitations

• two players on the same LAN
• GBA MULTI mode and Multi-Pak only
• exact ROM-byte matching
• Android ARM64/API 21+
• stock RetroArch with Netpacket command 78

Four-player sessions, Single-Pak multiboot, Wireless Adapter/RFU, internet relay, reconnection, host migration, and savestates during live sessions are not supported. Sensor inputs and wall-clock RTC observations are not synchronized, and the protocol-v2 wire contract is not frozen.

This is intentionally an experimental compatibility alpha, not a claim that every Multi-Pak title works. The attached .gba files are redistributable CC0 diagnostics. See INSTALL-AND-USAGE.md and SHA256SUMS in the bundle for full instructions and verification.