About Lag Reduction Options
Currently, there are 2 options. They increases speed, but they also causes a trouble for some games (for example: impossible to boot), because of whatever DeSmuME's bad timing emulation.

- Fix ARM Cycle Count
This fixes the wrong cycle counting in armcpu_exec and instruction cycles of {S} instructions. It's not a sort of hack, but some games don't boot if it's enabled.

- Fast Fetch-Execute
If enabled, the emulator will process fetch-execute cycle parallelly. It's implemented somewhat inaccurately (still closer than before, I think). It causes an emulation glitch for some games. I recommend not using this option for now, since DMA transfer sometimes doesn't work well in fast speed (for instance, the above map screen of Castlevania OoE will be rendered a bit glitchy). Fix ARM Cycle Count will work enough for normal play.

These options will not be recorded to a movie.

• DS emulator for PC: DeSmuME v0.9.2
  

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