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frsj8112

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I was thinking about the old Major Title to R-type and R-type 2 conversions.
The R-type 2 conversion is pretty clean, no extra wires and such. But the R-type conversion is pretty messy. Extra TTLs and RAM and alot of wiring. Can this conversion be cleaner with a patched PAL?

And yes, I'm calling for Apocalypse on this one ;)
 
I was thinking about the old Major Title to R-type and R-type 2 conversions.
The R-type 2 conversion is pretty clean, no extra wires and such. But the R-type conversion is pretty messy. Extra TTLs and RAM and alot of wiring. Can this conversion be cleaner with a patched PAL?

And yes, I'm calling for Apocalypse on this one ;)
It's probably worth having a look.
 
I have been working on dragon breed / major title conversion.

Very close however there are graphics / banking / priority that are not understood in mame.


The functions 8c etc, E4000 / B4000 (82 / 84)

Was going to run some games with the functions missing to see what they did but have ran out of time at the moment.
 
Just finished converting Dragon Breed, wish I had seen your post before starting though Hammy as probably could have helped you finish off your work rather than doing my own!
Just need to burn the roms and try it on a real board as so far I have just been running it in Mame as Major Title with renamed roms.
I also haven't bothered remapping the tile tables so at the moment you need to have the single high/low roms in both 0 & 1 sockets on the MT board.
It also should not need any mods to the board unlike R-Type.
Just need to sort out the high score saving as well. I did this on my R-Type conversion by replacing one of the work rams with an NV version.
 
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Just finished converting Dragon Breed, wish I had seen your post before starting though Hammy as probably could have helped you finish off your work rather than doing my own!
Just need to burn the roms and try it on a real board as so far I have just been running it in Mame as Major Title with renamed roms.
I also haven't bothered remapping the tile tables so at the moment you need to have the single high/low roms in both 0 & 1 sockets on the MT board.
It also should not need any mods to the board unlike R-Type.
Just need to sort out the high score saving as well. I did this on my R-Type conversion by replacing one of the work rams with an NV version.
Cool, you could of asked for the roms or a commented patch file and saved on time... It's there if you need it...

Mame and the pcb are totally different so sadly i doubt it will work first go. (see my older vids of it working BETTER in mame than the pcb testing went)
Turns out that the GFX1 and 2 are swapped on the major pcb compared to the m81 for a start.

I also doubled up on the program roms, it's the only sane way of doing it.
 
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So now we make a M82 multi in some way with bank switching & dips perhaps?
I have an R-Type conversion i did, but i want to keep R-Type and also play Dragon Breed without spending $400. Choices choices..
Maybe @apocalyse can cook up some daughtercard(s) to shove into the 27C040 sockets again? ;)
 
So now we make a M82 multi in some way with bank switching & dips perhaps?
I have an R-Type conversion i did, but i want to keep R-Type and also play Dragon Breed without spending $400. Choices choices..
Maybe @apocalyse can cook up some daughtercard(s) to shove into the 27C040 sockets again? ;)
I think the best would be if @Apocalypse could re-use his design from System C2 into this project. If Eproms are equal in size and position, it would be a direct replace. If not, would need some tweaking. Actually if it was a direct replacement, he could just install 2 or 3 of the same kit as so many roms are needed.

Just my 2 cents.
 
Mame and the pcb are totally different so sadly i doubt it will work first go. (see my older vids of it working BETTER in mame than the pcb testing went)

Turns out that the GFX1 and 2 are swapped on the major pcb compared to the m81 for a start.

I also doubled up on the program roms, it's the only sane way of doing it.
Yes, I had a few occasions when Mames fiddles have caught me out in the past.
I have now changed the mapping so that you don't need to double the roms, wasn't too bad in the end only a few places to patch.
I removed the ram address line patch from my RType II converted MT then fired up the roms. What shit, the foreground layer wasn't visible and the background was sometime doubled and jumpy with the foreground layer missing. So decided to have a close look at Air Duel on the M82, thats when I found this....

Am pretty certain the VRam's are the right way around, just that there is an undocumented layer control register on port $8C, try writing a 0x0003 to it ;)

It now works perfectly, but only after a random reset which occurs either just after the initial tests or during the title screen. Looks like a watchdog reset but my RType had been perfect.
I have also looked for Out's to $8E but haven't found any yet so still uncertain what this register does.
Almost there now, just need to find out the reason for the initial boot fail & reset, just a pain as in Mame it works perfectly.
 
@Hammy and @GadgetFreak: I had many issues with MAME in the past. Although games seem to work perfectly from an end user point of view, I've discovered many flaws in emulation of Irem M72/M92/M107, Capcom CPS1, Sega System C2, etc.

@Asure, @Darksoft and @PascalP: A multi seems totally doable following the same principles I used for System C2. I have many Irem conversions needing testing on real hardware: all M72 games patched for no mcu (X Multiply reported working and released here), R-Type on "standard" M72 romboard, all M72 games patched for M81 hardware, etc. but I'm struggling finding M72/M81 boards for sale. The ultimate goal would be to have all M72/M81 games running on M82 hardware.
 
I just want to mention I went the "plug in the sockets" route because System C2 doesn't use a romboard.
Sometimes romboards can't be easily reproduced and the same trick has to be used (like DS multi CPS2).
However for System 16/18/24, I plan to reproduce romboards so only a working motherboard would be needed.
It's quite a bit of work for System 24 to support all games cause the redesigned romboard would have to be a romboard, floppy controller and steering wheel controller at the same time (they all plug to the same connector either on bottom or top side of the motherboard and can even be stacked). That or I design 3 separate boards working as 1:1 replacements.
 
very interesting...

Also more work than expected I guess....
 
Further to my earlier post about still having issues.....
The reset one was me being stupid! The board maps the second L/H eproms to the upper address range which is where the cpu starts executing code. So duplicates of the roms will be needed anyway.
But after this I still had the gfx glitches, it was like the OUT to $8C wasn't working. So I rewrote the startup code adding a delay before the OUTs like Air Duel and now I have an almost perfectly working Dragon Breed. The only glitch left is when the game screen is rendered as there is a very slight flicker as it renders the layers on the display. The M82 has a method for controlling this, it will just take a little time to find the patch points for it.

BTW I have also added permanent high scores as I had already replaced a work ram on my board with a non volatile version at location 9A, its a bit of a pain as it needs a to have dual chip select lines to work correctly.
 
Hammerin harry works great on the stock m82 pcb.. use the m72 pal and the m84 pal recently added to jammarcade and mame m82 set.

I think that this address map is better / less messing if you want to do the full set.... it's also an interesting case as it uses some of the other features as IREM intended a bit like air duel and major.
A 4 in 1 is possible right now on stock - major, harry, rt2 + air duel.. soon dragon breed and rtype after getting the hacks down.

X Multi and the other double GFX rom games will be interesting to figure out for the newer hardware, along with cosmic cop / kengo with the same chip as the m92/m107
Finishing dragon breed is top of my list tho.

@GadgetFreak
I was sending 10h down 8c, can bet that's not all thats missing - priority is a big problem here with this so it may clean it up a bit.
FWIW i noticed no difference with or without the 'RT2' single wire ram hack while testing dragon breed
Don't get any lock ups here just bad gfx mostly... after doing cps1 stuff learned always keep the game running before moving forward...

Nice one on getting the roms down, not worth the time normally but if the full set is what we're going for then keeping them down in size is important ;)
 
Nice one on getting the roms down, not worth the time normally but if the full set is what we're going for then keeping them down in size is important ;)
Can't it be circumvented by handcrafting a new PAL?
This is what I had to do for RT (M72) on standard M72 romboard as no other game shares the same mapping unless you double program ROMs and modify all RAM offsets.
 
Nice one on getting the roms down, not worth the time normally but if the full set is what we're going for then keeping them down in size is important ;)
Can't it be circumvented by handcrafting a new PAL?This is what I had to do for RT (M72) on standard M72 romboard as no other game shares the same mapping unless you double program ROMs and modify all RAM offsets.
Hacking the pal is a way, but for a multi a standard is required for all games to run i guess. Pals are also not something i'm good at, but had one or two lucky times with them ;)
 
FINISHED
Another difference between M81 and M82 is that display off is controlled by writing 0x0001 to $E4000 on an M82 whereas on an M81 its 0x08 to port 0x02.
So have found where DB was turning off the display to render the screen and patched the code. Game now works perfectly, never realised what a good game Dragon Breed is. Think I may have to keep it rather than changing back to RType II.
This will be released very shortly, just need to finish checking the patch info's in my Rom Patching program, it's up to 292 ROM sets covering 76 games now.
@Hammy can you PM me your email address if you want a copy of my patched Dragon Breed for testing.
 
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