.added YM2413 context to Master System savestates
.removed support for older savestates format (1.3.x, 1.4.x), use 1.5.0 to convert old savestates to new (1.5.x) format
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* improved VBLANK flag accuracy, as observed on real hardware.
* improved DMA operations accuracy, writes are now performed on a scanline basis: fixes Gaiares (flickering title screen).
* improved DMA Fill timing accuracy.
* fixed DMA with bad code values: fixes Williams Arcade Classics (corrupted gfx after soft reset).
* fixed horizontal resolution changes during HBLANK: fixes Bugs Bunny in Double Trouble (2nd stage).
* fixed Vertical Counter in interlace mode 1, as observed on real hardware.
* fixed horizontal border width, as observed on real hardware.
* various code improvments & optimizations.
[Core/Extra]
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* improved savestate format: added DMA, SVP, cartridge mapping & internal registers state informations
* improved unlicensed ROM mappers emulation
* added Chinese Fighters III mapper support
* added Top Fighter mapper support
* fixed Barver Battle Saga mapper support
* fixed cartridge hardware soft-reset (Game Genie, SVP, ...)
* fixed Game Genie registers byte reads
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* improved 68k accuracy (initial reset timing + auto-vectored interrupts handling).
* modified Z80 & 68k cores to directly use external cycle count instead of intermediate counters.
* improved Z80 & 68k cpu execution/synchronization accuracy, now use Master Clock as common clock reference.
* improved PSG & FM chips synchronization with CPU execution (fixed point precision).
* completely rewrote sound output processing & mixing: sound chips are now clocked with exact output frame rate
to ensure 100% smooth video & audio playback, with no lag or skipping, while still rendering an accurate number
of samples per frame. This will also make fast-forward implementation (video AND sound) more trivial.
* improved color accuracy in VDP highlight mode to match results observed on real hardware.
* improved sprites processing timing accuracy: fixes (un)masked sprites in Mickey Mania (3D level), Sonic 2 (VS mode).
* improved horizontal blanking & HINT/VINT occurrence timing accuracy, as measured on real hardware.
* improved H-Counter accuracy in 40-cell mode, as measured on real hardware.
* optimized Z80 bus status signals
* usual code cleanup
[GCN/WII]
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fixed ASNDLIB exit when returning to game
fixed audio/video startup sync
modified audio back-end engine according to new audio processing core (see above)
