Console add-ons and linking emulation are almost always difficult tasks. Worse yet, availability, software support, cost, and even popularity can limit the ability to get these hardware add-ons documented and emulated. While their are numerous examples spanning tons of consoles and their respective emulators, this month, we're talking about GameCube to Game Boy Advance Connectivity.
Timings and synchronization are a given on real hardware; games know how it's going to work and many expect it to always work perfectly. When it doesn't? Certain games break. Now imagine a synchronization task more complex than dualcore and netplay. That would be GBA to GCN connectivity.
When skidau took up the task of renovating Dolphin's connectivity to Visual Boy Advance-M, he knew that it would require not only work on the Dolphin side of things, but also VBA-M. Getting two completely different emulators to sync up (up to 5 instances!) and play nice was the heart of the issue. Months of prototype builds (over 60 total!) between Dolphin and VBA-M were tested and the best possible combination was chosen for high compatibility and reasonable performance. The result is Dolphin (and VBA-M) finally getting a taste of what this feature was like on console.
That, and much more, is featured in this month's progress report!