Genesis Core
Moderators: Mug UK, Zorro 2, spiny, Greenious, Sorgelig, Moderator Team
Re: Genesis Core
What's the benefit of turbo on console? All games are written for standard speed.
Re: Genesis Core
Tried mostly 3D games, and turbo CPU clock helps them. Look at Race Drivin' for example, or F117 Night Storm.
Re: Genesis Core
Sonic 1/2/3, splatter house 2 are prime examples.
Re: Genesis Core
Sorgelig, it makes spinball road rash and other games with slowdown/framerate issues run without slowdown.
Same as the superfx overclock or the Gradius III sa1 hack.
Same as the superfx overclock or the Gradius III sa1 hack.
Last edited by Grego2d on Tue May 14, 2019 5:02 pm, edited 1 time in total.
Re: Genesis Core
Also slingshot, if you look at my first attempt I'm just changing the rate of the clock, that version gives audio issues as well, so you might want to test on mister, this might only be an issue in the mister implementation.
Re: Genesis Core
I cannot do it, because I don't have one. I've checked Sonic1 on MiST, didn't notice anything unusual with CPU Turbo ON.Grego2d wrote:Also slingshot, if you look at my first attempt I'm just changing the rate of the clock, that version gives audio issues as well, so you might want to test on mister, this might only be an issue in the mister implementation.
Re: Genesis Core
Sorgelig, the only slow down in those games is when you lose a lot of rings. That's not what he's testing tho, overclocking causes audio issues in those games on mister.
Re: Genesis Core
Thank you for testing slingshot, how recent is your build of Genesis for mist? From the look of your code quite a bit is different.
Re: Genesis Core
I guess it would be prudent at this point to add an osd overclock option so I can see if audio problems clear up when disabled.
Re: Genesis Core
What kind of audio issues you have? which games?Grego2d wrote:Couple of attempts and I think I have Z80 communication fixed. Audio is still messed up in most games, but it's improved. I think the remaining issues are caused by the 68k accessing the psg directly, but I'm not sure.
Re: Genesis Core
Wrong pitch/garbled sounds, sonic 1 2 and 3, splatterhouse 2, gunstar heroes, most games are having issues.
Re: Genesis Core
Just noticed sound debug option in Genesis.sv, recompiling with that so I can test FM/PSG individually.
Re: Genesis Core
Well, after testing it's both the FM and PSG having issues, hmmmm
In both cases some sounds are fine and others are messed up, Sonic 2 the jump sound is fine, other psg music sounds are wrong.
In both cases some sounds are fine and others are messed up, Sonic 2 the jump sound is fine, other psg music sounds are wrong.
Re: Genesis Core
Added an osd option for turbo, turning off turbo after loading a game does fix the audio issues. Sorgelig, does the 68k access the FM chip directly as well as the PSG?
Last edited by Grego2d on Tue May 14, 2019 7:11 pm, edited 1 time in total.
Re: Genesis Core
More testing, now that I can control turbo from the osd I can see the psg is actually working correctly. Only FM sounds are a problem.
Interestingly, sonic spinball only uses the FM chip and it sounds fine besides being higher pitched.
And apparently road rash is similiar, fm only, audio plays back at higher rate when overclocked resulting in higher pitch.
Gonna try a new tactic, only accelerate ram/rom reads/writes.
Interestingly, sonic spinball only uses the FM chip and it sounds fine besides being higher pitched.
And apparently road rash is similiar, fm only, audio plays back at higher rate when overclocked resulting in higher pitch.
Gonna try a new tactic, only accelerate ram/rom reads/writes.
Re: Genesis Core
The FM chip gets the same clock enable on MiSTer, as the CPU PHI1 phase, and it is also doubled then. Don't double the FM clock, and it'll be good.Grego2d wrote:More testing, now that I can control turbo from the osd I can see the psg is actually working correctly. Only FM sounds are a problem.
Interestingly, sonic spinball only uses the FM chip and it sounds fine besides being higher pitched.
And apparently road rash is similiar, fm only, audio plays back at higher rate when overclocked resulting in higher pitch.
Gonna try a new tactic, only accelerate ram/rom reads/writes.
Re: Genesis Core
Oh damn, I had not noticed that
Made the change, compiling. Thanks so much for your help slingshot
Made the change, compiling. Thanks so much for your help slingshot

Re: Genesis Core
Assuming this works I'll clean up the code and send a pull request to Sorgelig shortly.
Re: Genesis Core
Works perfectly, this is awesome, code cleanup and pull request incoming.
Here's a working build in the mean time:
https://ufile.io/2h7up0ic
Did some more testing, it's the small things that are surprisingly impressive. Quicker load times on menus, toe jam and Earl goes to map twice as fast. Less lag in tight situations, splatter house 2 turn around ghosts cause no lag at all. Quite an improvement. So far the only game I've found to have an issue is earthworm Jim, slight hiccups in the audio.
Sorgelig, points at which Sonic 2 lags:
Losing too many rings
Tubes on chemical plant zone
Water rising on chemical pz
Bonus stages
Here's a working build in the mean time:
https://ufile.io/2h7up0ic
Did some more testing, it's the small things that are surprisingly impressive. Quicker load times on menus, toe jam and Earl goes to map twice as fast. Less lag in tight situations, splatter house 2 turn around ghosts cause no lag at all. Quite an improvement. So far the only game I've found to have an issue is earthworm Jim, slight hiccups in the audio.
Sorgelig, points at which Sonic 2 lags:
Losing too many rings
Tubes on chemical plant zone
Water rising on chemical pz
Bonus stages
Re: Genesis Core
I would have sent a pull request by now Sorgelig, however I did some minor refactoring and now Quartus won't produce a usable binary. I even reverted all my changes back to the working code and it produces cores that do nothing. Kind of at a loss here, just nuked my db/output_files/incremental_db folders, well see if that helps.
Re: Genesis Core
Let me implement the Turbo by myself.
I know the core, so will do it.
It's just the feature i didn't think before. But not hard to implement.
Real turbo needs to include other tweaks. For example disable vdp fifo.
I know the core, so will do it.
It's just the feature i didn't think before. But not hard to implement.
Real turbo needs to include other tweaks. For example disable vdp fifo.
Re: Genesis Core
Sure, go ahead, was just trying to learn/help.
Btw did you try the build I posted on any of the games that have slowdown?
And out of curiosity, why would you need to disable the vdp fifo?
Btw did you try the build I posted on any of the games that have slowdown?
And out of curiosity, why would you need to disable the vdp fifo?
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I didn't express correctly. I mean disable fifo throttling.
I didn't try your build yet.
I didn't try your build yet.
Re: Genesis Core
Ok, figured out the issue finally. Jesus, if you can't find a var Quartus throw a error not a warning...
Gonna send you a pull request when it's working anyway Sorgelig. If you use some of it cool, if not, no worries.
Gonna send you a pull request when it's working anyway Sorgelig. If you use some of it cool, if not, no worries.