blisstik commented 1 year ago

I'm looking at d_cps1.cpp. Shouldn't nCPS68KClockspeed be set to 7899600 instead of 790000 to get 65.83%? Can that be tested so it's as close to PCB as possible?

static INT32 Sf2hfInit()
{
    // game runs too fast - RN compared MAME/FBA to PCB
    // RN October 2018 research: adjust excessive speed to 65.83% of 12Mhz as per: https://www.youtube.com/watch?v=HyL87eswe8M

    nCPS68KClockspeed = 7900000;

    return DrvInit();
}

The initial value

static INT32 TwelveMhzInit()
{
    nCPS68KClockspeed = 12000000;

    return DrvInit();
}

blisstik commented 1 year ago

Doing some math, I guess if the intent is 65.833333333% then its right.

dinkc64 commented 1 year ago

I'm not sure how accurate the comment is, but I remember that RN did a lot of work getting that value right

blisstik commented 1 year ago

There’s a couple videos that RN did. The 7.9Mhz was the first. Then he tested 8.5Mhz on another video which had less variance. Do you mind if I submit a PR to 8.5? I’ll reference that video from RN.

blisstik commented 1 year ago

1256

dinkc64 commented 1 year ago

Nice, I must have missed his newer videos, thanks :)

finalburnneo / FBNeo

SF2HF Speed #1253

1256