Genesis.. Drmd Is The Bomb?

[skeezix]

I've not been keeping up with the Genesis emus on the GP32 (my GP keeps wiping out my SMC card, so it currently only has my CaSTaway stuff, and some of the last compo's like Akanoid

I've not tried DrMD or whichever it is; is that the best Geensis emu right now, or is it not a clearcut winner?

I never had a Genesis so when I started playing those games I was ratehr surprised, a year or so back; then I of course ported a couple genesis emus to various platforms and life hsa been good; I just a month back got a Genesis emu for my PS2, and *damn* it kicks ass over the other emus I've used.. the sound is simply amazing. Seams all the Genesis emus I've been used to have been missing half or more of the audio. (ie: Most people port Charles MacDonalds Genesis Plus emu, which is very compatible, but lacks most of the audio.) I think Generator has better audio emulation, but not sure anyones ported it. I think Rlyeh's fGen is just Genesis Plus again, but probabyl tweaked all up so maybe hes added in some of the missing audio. (And hey, rlyeh, if you have, send me the source.. maybe I coudl beef up my Genesis Plus ports

So now I'm spoilt.. I need a Genesis emu with good (not missing) audio.

Which one is the best to try?

jeff

 

[Goity]

DRMD has all sound apart from the Segaaaaa at the start of sonic. Fgen has half sound

 

[skeezix]

Why would he be missing the Seeegggaaaa? That would suggest a number of subsystems could be missing?

I guess I need to figure out where to get DrMD; did EvilDragon ever get his file archive fully populated?

jeff

 

[Alpha2]

It's still a toss up, there are som games one does better than the other but over all sound seems to be the one sticking point so far as I can tell. Neither DrMD or Fgen has the music in cool spot, I think Fgen plays Gunstar Heroes a little better. I just keep both on my card and see which one runs each rim better on a case by case bassis.

 

[pAiN]

as a personal preference I like DRMD, but I don't like autoframeskip. Speed wise, i can play sonic1 w/sound at 132mhz on FGEN and it runs perfectly or I can run DRMD with autoframeskip at 156mhz and it will be to choppy and fast. Gunstar heroes at 156mhz is to choppy and fast with autoframeskip. If a new version would be released with an option to change the frameskp i would be a happy camper and wouldn't need anything else. I'm sure my GP could run any game full speed with sound at frameskip 2 at the highest.

EDIT: thought i would add this in. WHen i play emus on my IPAQ, autoframeskip is the default option and it runs horrible, once turned off the emus play fine and at full speed. So i for one never would recommend adding autoframeskip to an emu.

 

[skeezix]

Depends how its implemented.. an auto-frameskip is difficult to poll off due to low resolution or inaccurate timers in most platforms.

ie: My CaSTaway auto-frameskip for Palm OS is cheesy, but seams to work very well.. if a frame gets ahead it just spins for a part-of-a-second and continues; thats a pretty naive system, but .. on my 400-600MHz T|T3, CaSTaway runs pretty much spot on (maybe a couple frames slow or fast depending, so you'd never notice). Having to futz with frameskip directly on 400-600MHz was a pain since it was hard to tweak for each game.

So "your mileage may vary" I guess

Does DrMD use the same rompath as fGen? If so, that makes it easy

jeff

 

[Reesy]

I think the best idea is to have Fgen and DrMD on your smc.

Fgen is faster, but less compatible because

a) It does not emulate the Z80
B) Line interupts are not emulated, meaning the M68K is core run for the whole frame reducing the overhead of having to stop and start the CPU.
c) The graphics rendering is done on a frame by frame basis. ( Done in very fast C code - I've seen the source )

DrMD is slower, but more compatible because

a) Its emulates the Z80
B) It emulates line interupts
c) The graphics rendering is done on a line by line basis.

Both Fgen and DrMS use the exact same sound core. This is a optimised version of the Mame sound core written by Rob Brown. Currently support for the DAC chip has been removed from the core in order to increase speed. This is why you don't get any voice samples. Even though the FM is very optimised it still takes a serious amount of CPU time. An example:

Sonic 1 on DrMD 133Mhz Sound Off = 45 - 50 FPS
Sonic 1 on DrMD 133Mhz Sound On = 15 - 20 FPS

One of the things I want to do is take the source Rob Brown has written and re-write in Assembler to see if I can get it running faster. This will probably be the next thing I do after completing the UI. Hopefully during the re-write I will gather enough understanding of the sound chip to add support for the DAC back in.

Of course Fgen has saves states and the current version of DrMD does not. This is an important point.

With regards the "auto frame skip" issue. I'll put in the manual frame skip if enough people want it. I just hate using it the speed of the emulator becomes un-predictable, ie one minute its fast the next its crawling.

Later

Reesy

 

[Antiriad]

It does indeed use the same Roms path - Genesis being the folder name.
And the thing its missing to play samples such as Seeeeega is the DAC.

 

[Reesy]

Oh another point Fgen supports zips and DrMD does not. What's your email address skeezix? Fancy a beta of my latest version - Zip support and animated save states ( uncompressed at the moment - though ).

 

[Reesy]

Yep the Z80 has access to the YM2612 sound chip. The Z80 uses the DAC on the YM2612 to create the voice samples. The Z80 in itself does not "create sound", it is not a sound chip. It is used to drive the sound chips, which in turn takes the load of the M68K. Freeing it up to do other cool stuff.

EDIT
Sorry this looks like I'm talking to myself, but someone "who shall remain nameless" deleted their post in order to make me look foolish

 

[Memnoch]

Sorry I just wanted to post here to be in the presence of such gods as skeezix, Reesy and Squidge

 

[skeezix]

Menoch - heh

The DAC shouldn't be too hard to handle.. samples are fast to process of course, but its a pin to get their timing right.. but the Z80 Genesis audio system is screwy and I've never wanted to look into it much, just relied on other peoples work on that front

reesy -- skeezix@codejedi.com should work well, and now that its posted I'll get more spam for my filters to eat

jeff

 

[tekt5]

What's your email address skeezix? Fancy a beta of my latest version - Zip support and animated save states ( uncompressed at the moment - though ).

Hey Reesy I'll take one of those!! :rolleyes:

Great Emu by the way!

Sorry I just wanted to post here to be in the presence of such gods as skeezix, Reesy and Squidge tongue.gif

I agree with you on that!


edit:

By the way.. what ever happended to Gigadrive?

 

[pAiN]

as far as i know i think i'm the only person that has problems with the auto frameskip, but as far as i'm concerned, with the games i've played, that a frameskip option is the only thing keeping this emu from perfect in my eyes. I like the sound and everything else. Saves and zip support is not important to me. So please, if you have time, i wish to see a frameskip option.

Thanks Reesy for the great emu.

 

[Goity]

no, the game runs too fast and the sound too slow

 

[lizard808uk]

I think both emus are great. Its like Snes9x vs Zsnes (btw zSnes now has Sdd1 for Star Ocean!), but for GP32.

There are plenty of games that run really well full speed and sound in DrMD. (I mentioned World of Illusion in another thread).

Are they any custom chips in games to emulate or does the genesis stick to what its got under the hood? (I know about VF, but are there others?)

 

[shinneri]

Hey, Reesy, is there a tentative release date for this awesome new version of DrMD?

Oh, and does anyone know what Rlyeh's up to? I know a couple weeks ago before the 16 Days comp ended there was a lot of talk about a fGen with Z80 support and the first beta of fMame, but I haven't heard much recently..

 

[Reesy]

I've just got to compress the save states and track down this bloody annoying screen bug where the screen gets scrolled weirdly. Then I make a release, should be in a few weeks.. maybe even a fortnight.

 

[Dozer]

I've just got to compress the save states and track down this bloody annoying screen bug where the screen gets scrolled weirdly. Then I make a release, should be in a few weeks.. maybe even a fortnight.

​

Sweet . Good luck with it and thanks for the work you've done so far. Cracking emulator. 1 of the best.

 

[DaveC]

Menoch - heh

The DAC shouldn't be too hard to handle.. samples are fast to process of course, but its a pin to get their timing right.. but the Z80 Genesis audio system is screwy and I've never wanted to look into it much, just relied on other peoples work on that front

reesy -- skeezix@codejedi.com should work well, and now that its posted I'll get more spam for my filters to eat

jeff

​

Honestly I could be very happy without DAC support. If DAC slows down the emu at all I would say it is not worth it for having the "Sega" and a few voices here and there. But that is just me.