DreamShell v4.0.2 Release

[sundance2]

Long time user of Dreamshell here,
I've been inactive for a few years,
and just came back recently to discover v4.0.2.

Just wanted to report my experience using this new version in combination with a Serial port adapter and a SD card.

And it's a solid improvement all around.

Many games that were "on the limit" now work fine, very fluid.

Something happened with regards to the Serial interface performance.
Benchmark shows an improved read throughput from ~650 KB/s to ~750 KB/s.
No magic, but every bit help, and this is a very welcome improvement.

I also wonder if latency has been improved. Performance seems very good even with low async values, which in turn considerably favor in-game fluidity.
My favorite setting seems to rapidly converge towards `async 2`, which is both low enough that there is no stuttering in game (some slow down can happen, but even then, it's just slower but still fluid), and offer sensible throughput improvement compared to `async 1`. `async 4` seems to be too much, with stuttering now perceptible again. Haven't tested `async 3` yet, though I'm not expecting much, since throughput seems barely improved from 2 to 4.

An example of bug triggered by performance issues: Donald Duck Quack Attack, used to have some minor yet annoyingly perceptible stutter in game. More importantly, over time, the camera would slowly drift away from the main character (Donald), to the point of making the game unplayable. That's no longer the case: everything is fluid, both videos and gameplay, and no more drift at all in game, making the game finally fully playable and enjoyable.

DoA2 is also all fluid, some slowdown can still happen during scene transition (when jumping from one level to another for example), but most sequences are very fluid.

Not all is perfect of course, for example I have not yet been able to make CDDA work with Ms Pacman (though I barely had time to test it).

All around, it's a very solid upgrade, and highly welcome. It will definitely make me play more with my original and still unmodified Dreamcast (which is why i use the serial port).