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mist-devel / fpgagen

SEGA Genesis/Megadrive core, running on the MIST
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Time multiplexed output for JT12 (boosts gain) plus decreased volume for PSG #36

Closed jotego closed 5 years ago

jotego commented 5 years ago

Real YM2612 had a time multiplexed channel output. This option is also present in JT12. The advantage of this option is that when channels are mixed in the speaker, the result is that each YM2612 channel sounds with an attenuation of 1/6 over the total. In comparison, when the continuous time output is used, channel volume is attenuated by 1/8. Mux'ed output has a +2.5dB gain increase with respect to continuous time output.

Mux'ed output will affect a bit the "colour" of the sound, but that's exactly what real hardware did so this moves it closer.

I have also decreased the gain of the PSG so games sound better. Titles like Streets of Rage, which combines PSG and FM instruments, sound better now.

harbaum commented 5 years ago

This expects jt12 to be placed somewhere outside the source tree. Why has this been done? This at least requires documentation which files have to be placed where.

jotego commented 5 years ago

Sorry, that's my fault because of how I organized my folders. That doesn't need to go into the merge. It is just that I don't know well how to handle one git repository inside another so I just use a symbolic link in FPGAgen to point to my JT12 repository.

El lun., 5 nov. 2018 a las 8:08, Till Harbaum (notifications@github.com) escribió:

This expects jt12 to be placed somewhere outside the source tree. Why has this been done? This at least requires documentation which files have to be placed where.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/harbaum/fpgagen/pull/36#issuecomment-435774667, or mute the thread https://github.com/notifications/unsubscribe-auth/ABxtfBKUHKNm1QPvLty-SubiVILJKmjMks5ur-P_gaJpZM4YNiKO .

harbaum commented 5 years ago

Neither me. But i now have to figure out how to clean this up ...

jotego commented 5 years ago

If you prefer it, just revert the merge and manually copy the virtual top vhd file. I’ll be more careful the next time.

El El lun, 5 nov 2018 a las 11:33, Till Harbaum notifications@github.com escribió:

Neither me. But i now have to figure out how to clean this up ...

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gyurco commented 5 years ago

@jotego handling submodules is like any other commits:

  1. go to the jt12 directory, it's a full git tree, you can pull, rebase, etc... from your upstream repo. You can even work in it, commit changes, and push to upstream.
  2. do a git checkout to the appropriate commit (or just use the current HEAD, if you work there).
  3. in the top-level, just do a git add jt12, git commit.