Drmd Version 2.0


This is AWESOME news that has so much significance for emulation. I hope this goes well. Not only would the fantastic DrMD benefit but also other emus like MAME, CaSTaway etc.

Good Work :)
 
Reesy posted on Jun 13 2005 said:
The days of a Cyclone related emulation problems may soon be over.....

I finally got around to writing a debug program yesterday and so far its working like a dream. I've got the cyclone core running alongside the Musahi core in a debug version of DrMD. I'm running 1 opcode on Musashi and then 1 on cyclone and checking for any differences. I had some problems with interupt timings but got around it by re-writing the interupt handler in Musashi and its working now.

Sar far its found bugs with asl,asr,lsl,lsr,roxl, moveq. At the moment I've only FOUND the bugs, so I've still got to fix them but things are looking up.

​
Click to expand...

SWEET!

Reesy - I HOPE this somehow leads to the fix of the only bug that's ever bothered me in DrMD... you know the one I'm talking about :D that scrolling bug with the giant airship in the third stage of Gunstar Heroes. One bit of possible bad news about that bug though. I don't remember if I mentioned this to you or not. I had you send me the musashi core DrMD to try this out on and verify if it was a Cyclone bug, but I got the same bug in Musashi.

However, I have since tried the game in fGEN, and it does NOT have the scrolling bug with the airship. So it's not a Cyclone bug but it works fine in fGEN.

are the chances good that the debugger might be able to find this particular problem?

Also, would the debugger find anything related to the transparency effects in the sonic games? That was actually something you did deliberately right and not a bug?
 
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The problem with Gunstar Heroes is a problem with my rendering code. I'm not sure what my rendering code is missing, have you sent me a save state yet? if you could send me one, I might have a look at it.

My debugger will only find problems with the cpu core, not with any thing else.
 
bast525 posted on Jun 14 2005 said:
Reesy posted on Jun 13 2005 said:
The days of a Cyclone related emulation problems may soon be over.....

I finally got around to writing a debug program yesterday and so far its working like a dream.   I've got the cyclone core running alongside the Musahi core in a debug version of DrMD.  I'm running 1 opcode on Musashi and then 1 on cyclone and checking for any differences.  I had some problems with interupt timings but got around it by re-writing the interupt handler in Musashi and its working now.

Sar far its found bugs with asl,asr,lsl,lsr,roxl, moveq.  At the moment I've only FOUND the bugs, so I've still got to fix them but things are looking up.

​
Click to expand...

SWEET!

Reesy - I HOPE this somehow leads to the fix of the only bug that's ever bothered me in DrMD... you know the one I'm talking about :D that scrolling bug with the giant airship in the third stage of Gunstar Heroes. One bit of possible bad news about that bug though. I don't remember if I mentioned this to you or not. I had you send me the musashi core DrMD to try this out on and verify if it was a Cyclone bug, but I got the same bug in Musashi.

However, I have since tried the game in fGEN, and it does NOT have the scrolling bug with the airship. So it's not a Cyclone bug but it works fine in fGEN.

are the chances good that the debugger might be able to find this particular problem?

Also, would the debugger find anything related to the transparency effects in the sonic games? That was actually something you did deliberately right and not a bug?
​
Click to expand...


The "transparency" bug is because it is not really transparency but a pallete switch (ever notice that this "transparency" is always horizontal and across the whole screen?). On a MD some games will switch the pallete on a scan line to a new pallete. The problem there is that the GP32 scans vertically (portrait) while a MD scans horizontal. This means that the emu would have to switch the pallete per pixel which would slow down the emu to a crawl. So the solution was to have the emu update the pallete once per frame and eliminate the mid-stream pallete switch.
 
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Reesy posted on Jun 14 2005 said:
The problem with Gunstar Heroes is a problem with my rendering code. I'm not sure what my rendering code is missing, have you sent me a save state yet? if you could send me one, I might have a look at it.

My debugger will only find problems with the cpu core, not with any thing else.
​
Click to expand...

Nope never sent you a save state, you don't need one to see this bug. The first four stages of Gunstar Heroes are freely selectable the right at the beginning of the game. Start it up and pick the third stage from the left, the airship level, it shows the picture of the boss is the muscle man in the military green/camo outfit. As soon as the stage begins, the screen will start to scroll upward, and you'll see the air ship on the right 'bug out', not really sure how to describe what it does but it's very obvious you'll notice it right away :D It doesn't scroll properly.

If you still want I can send you a save state no problem, gladly... anything for the chance that this bug might be fixed! Gunstar Heroes = best MD action game EVAR! :D :p
 
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Ahh thats okay, as long as the error is easy to get to then I won't need a save state. Once I've fixed cyclone ( approx 1 week, maybe 2 ), I'll have a look.

Cyclone News
----------------
Divu and Divs now fixed, overflows were not being detected. Road Rash 2 now plays correctly :)
 
Yeah, but Brian Lara is the game we're all holding out for, surely? Am I right or am I right????

Come on guys, back me up here...
 
This is missing an opcode. You get to play a game but as the first bowl comes in it tries to use an un-implemented opcode ( a movem opcode ). I'll add this opcode to my list of new ones to add.

Anyway Sensible soccer now works, and Dune, and Populous. Thats all I've tried so far but its looking good.

Opcodes fixed
asl,asr,lsl,lsr,roxl,roxr
divu,divs - fixes Road Rash 1 and 2

Opcodes added

cmpm - fixes Sensible Soccer, Dune, Populous

Opcodes to implement
Stop - Thunder Force 4
Movem - Brian Lara
Adda - Street Fighter Championship Edition

Its soo exciting isn't it. :)
 
Fucking great news!!
Now, if you fix Mega Turrican, I'll be the happiest man in the world.
 
Jaw posted on Jun 15 2005 said:
WOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOT!!
you rule!! megadrive's 3rd best game! i prefer zero tolrence to doom! more depth to it

​
Click to expand...


I think there is another game like this called "blood shot" or "battle frenzy" that worked but the polygons would "wig out" when you got close.

It looked awesome though I bet this would now work too :)

Wow this is great news though.

Maybe we should donate cash or sacrifice a goat to Reesy or something, he is a l337 coding god.

YOU RULE! Reesy, Thanks for everything!
 
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